Researchers Database

SUGIURA, Miwa

    Proteo-Science Center Associate Professor
Last Updated :2020/10/13

Researcher Information

J-Global ID

Research Interests

  • 水素   電子伝達   生体エネルギー変換   光合成   

Research Areas

  • Life sciences / Biophysics

Academic & Professional Experience

  • 2013/04 - Today  Ehime UniversityProteo-Science Center准教授
  • 2010/10 - 2016/03  科学技術振興機構ーさきがけ研究員(兼任)
  • 2010 - 2016  JST-PRESTO
  • 2008/05 - 2013/03  Ehime UniversityCell-Free Science and Technology Research Center准教授
  • 2010/04 - 2011/03  The Open University of Japan講師(兼任)
  • 1999/04 - 2008/04  Osaka Prefecture UniversityGraduate School of Life and Environmental Sciences助教
  • 2005 - 2007  Osaka Prefecture UniversityGraduate School of Life and Environmental Sciences
  • 2000 - 2005  大阪府立大学大学院 農学生命科学研究科
  • 1999 - 2000  大阪府立大学大学院 農学研究科
  • 1997 - 1999  理化学研究所
  • 1997 - 1999  RIKEN
  • 1999  Tokyo University of Agriculture and TechnologyFaculty of Engineering

Education

  •        - 1997  Kobe University  自然科学研究科  生命機能化学
  •        - 1997  Kobe University  Graduate School, Division of Science and Technology
  •        - 1994  Kobe University  理学研究科  生物学
  •        - 1994  Kobe University  Graduate School, Division of Natural Science

Association Memberships

  • 日本ナノ学会   フランス光合成学会   国際光合成学会   アメリカ植物生理学会   日本光合成学会   日本化学会   日本生物物理学会   日本植物生理学会   

Published Papers

  • Miwa Sugiura, Tomonori Taniguchi, Nanami Tango, Makoto Nakamura, Julien Sellés, and Alain Boussac
    Physiol. Plant. in press 2020/04 [Peer-reviewed]
     Scientific journal
  • Boussac, A., Sellés, J., and Sugiura, M.
    Biochim. Biophys. Acta (Bioenergetics) 1861 148176  2020 [Peer-reviewed]
     Scientific journal
  • Proton release process during the S2-to-S3 transition of photosynthetic water oxidation as revealed by the pH dependence of kinetics monitored by time-resolved infrared spectroscopy
    Takemoto, H, Sugiura, M, Noguchi, T
    Biochemistry 58 4276 - 4283 2019 [Peer-reviewed]
     Scientific journal
  • An alternative plant-like cyanobacterial ferredoxin with unprecedented structural and functional properties
    Motomura, T, Zuccarello, L, Sétif, P, Boussac, A, Yasufumi, U, Lemaire, D, Tripathy, J.N, Sugiura, M, Hienerwadel, R, Shen, J.R, Berthomieu, C
    Biochim. Biophys. Acta (Bioenergetics) 1860 2019 [Peer-reviewed]
     Scientific journal
  • Consequences of structural modifications in cytochrome b559 on the electron acceptor side of Photosystem II
    Nakamura M, Boussac, A, Sugiura, M
    Photosynth. Res. 139 475 - 486 2019 [Peer-reviewed]
     Scientific journal
  • New insights on ChlD1 function in Photosystem II from site-directed mutants of D1-T179 in Thermosynechococcus elongatus
    SUGIURA Miwa
    Biochim. Biophys. Acta (Bioenergetics) 1860 309 - 309 2019/01 [Peer-reviewed]
     Scientific journal
  • Alain Boussac, Ilke Ugur, Antoine Marion, Miwa Sugiura, Ville R.I. Kaila, A. William Rutherford
    Biochimica et Biophysica Acta - Bioenergetics 1859 (5) 342 - 356 1879-2650 2018/05 [Peer-reviewed]
     Scientific journal 
    In Photosystem II (PSII), the Mn4CaO5-cluster of the active site advances through five sequential oxidation states (S0 to S4) before water is oxidized and O2 is generated. Here, we have studied the transition between the low spin (LS) and high spin (HS) configurations of S2 using EPR spectroscopy, quantum chemical calculations using Density Functional Theory (DFT), and time-resolved UV-visible absorption spectroscopy. The EPR experiments show that the equilibrium between S2 LS and S2 HS is pH dependent, with a pKa ≈ 8.3 (n ≈ 4) for the native Mn4CaO5 and pKa ≈ 7.5 (n ≈ 1) for Mn4SrO5. The DFT results suggest that exchanging Ca with Sr modifies the electronic structure of several titratable groups within the active site, including groups that are not direct ligands to Ca/Sr, e.g., W1/W2, Asp61, His332 and His337. This is consistent with the complex modification of the pKa upon the Ca/Sr exchange. EPR also showed that NH3 addition reversed the effect of high pH, NH3-S2 LS being present at all pH values studied. Absorption spectroscopy indicates that NH3 is no longer bound in the S3TyrZ [rad] state, consistent with EPR data showing minor or no NH3-induced modification of S3 and S0. In both Ca-PSII and Sr-PSII, S2 HS was capable of advancing to S3 at low temperature (198 K). This is an experimental demonstration that the S2 LS is formed first and advances to S3 via the S2 HS state without detectable intermediates. We discuss the nature of the changes occurring in the S2 LS to S2 HS transition which allow the S2 HS to S3 transition to occur below 200 K. This work also provides a protocol for generating S3 in concentrated samples without the need for saturating flashes.
  • Masaru Kato, Hisako Sato, Ichizo Yagi, Miwa Sugiura
    Electrochimica Acta 264 386 - 392 0013-4686 2018/02 [Peer-reviewed]
     Scientific journal 
    Photosynthesis converts solar energy into chemical energy. Photosystem II (PSII) oxidizes water to produce oxygen, electrons and protons under solar light irradiation. This light-driven water oxidation initiates a series of reactions in photosynthesis. Basic photoelectrochemical studies on PSII are directed toward the enzymatic applications of PSII for sustainable production of electricity or solar fuels. To maximize the photoelectrochemical catalytic activity of PSII on electrode substrates, interfacial designs between PSII and electrode substrates are important. Herein, we report bio-inorganic photoanodes of PSII and ferricyanide-intercalated layered double hydroxide (LDH) for visible-light-driven water oxidation. PSII is simply drop-cast onto a ferricyanide-intercalated cobalt–aluminum LDH and then shows a turnover frequency of 0.5 ± 0.1 s−1 and a turnover number of 920 ± 40 for 1 h at pH 6.5 at +0.5 V vs. NHE under visible light irradiation. Photoelectrochemical experiments using a PSII inhibitor or a bio-engineered PSII suggest that interfacial electron transfer from the plastoquinone QA site of PSII to ferricyanide may play an important role in improving the photo-electrocatalytic activity and stability of PSII. Our studies will open up new possibilities in fundamental or advanced photoelectrochemical studies of PSII.
  • Probing the role of Valine 185 of the D1 protein in the Photosystem II oxygen evolution
    Sugiura, M, Tibiletti, T, Takachi, I, Hara, Y, Kanawaku, S, Sellés, J, Boussac, A
    Biochim. Biophys. Acta (Bioenergetics) 1859 1259 - 1273 2018 [Peer-reviewed]
     Scientific journal
  • Mechanism of proton-coupled electron transfer in the S0-to-S1 transition of photosynthetic water oxidation as revealed by time-resolved infrared spectroscopy J. Phys. Chem. B
    Shimizu, T, Sugiura, M, Noguchi, T
    J. Phys. Chem. B 122 9460 - 9470 2018 [Peer-reviewed]
     Scientific journal
  • Arif Md. Rashedul Kabir, Masaki Ito, Kyohei Uenishi, Shizuka Anan, Akihiko Konagaya, Kazuki Sada, Miwa Sugiura, Akira Kakugo
    CHEMISTRY LETTERS 46 (2) 178 - 180 0366-7022 2017/02 [Peer-reviewed]
     Scientific journal 
    We have demonstrated in vitro motility assay of microtubules on a kinesin-coated substrate by using adenosine triphosphate (ATP) generated from microsphere gels containing thylakoid membranes. Upon photoirradiation, the gels generated ATP, which was utilized for performing gliding motions of microtubules. This work may facilitate the development of a localized ATP generation system in the in vitro motility assay, which consequently would widen the applications of biomolecular motors in nanotechnology.
  • Taiki Motomura, Michihiro Suga, Rainer Hienerwadel, Akiko Nakagawa, Thanh-Lan Lai, Wolfgang Nitschke, Takahiro Kuma, Miwa Sugiura, Alain Boussac, Jian-Ren Shen
    Journal of Biological Chemistry 292 (23) 9599 - 9612 1083-351X 2017 [Peer-reviewed]
     Scientific journal 
    Photosystem II catalyzes light-induced water oxidation leading to the generation of dioxygen indispensable for sustaining aerobic life on Earth. The Photosystem II reaction center is composed of D1 and D2 proteins encoded by psbA and psbD genes, respectively. In cyanobacteria, different psbA genes are present in the genome. The thermophilic cyanobacterium Thermosynechococcus elongatus contains three psbA genes: psbA1, psbA2, and psbA3, and a new c-type heme protein, Tll0287, was found to be expressed in a strain expressing the psbA2 gene only, but the structure and function of Tll0287 are unknown. Here we solved the crystal structure of Tll0287 at a 2.0 Å resolution. The overall structure of Tll0287 was found to be similar to some kinases and sensor proteins with a Per-Arnt-Sim-like domain rather than to other c-type cytochromes. The fifth and sixth axial ligands for the heme were Cys and His, instead of the His/ Met or His/His ligand pairs observed for most of the c-type hemes. The redox potential, E12, of Tll0287 was 255 ± 20 mV versus normal hydrogen electrode at pH values above 7.5. Below this pH value, the E12 increased by ≈57 mV/pH unit at 15 °C, suggesting the involvement of a protonatable group with a pKred 7.2 ± 0.3. Possible functions of Tll0287 as a redox sensor under microaerobic conditions or a cytochrome subunit of an H2S-oxidizing system are discussed in view of the environmental conditions in which psbA2 is expressed, as well as phylogenetic analysis, structural, and sequence homologies.
  • Miwa Sugiura, Yui Ozaki, Fabrice Rappaport, Alain Boussac
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1857 (12) 1943 - 1948 0005-2728 2016/12 [Peer-reviewed]
     Scientific journal 
    Two mutants, D1-H198Q and D1-H198A, have been previously constructed in Thermosynechococcus elongatus with the aim at modifying the redox potential of the P-680(center dot+)/P-680 couple by changing the axial ligand of P-D1, one the two chlorophylls of the Photosystem II primary electron donor [Sugiura et al., Biochim. Biophys. Acta 1777 (2008) 331-342]. However, after the publication of this work it was pointed out to us by Dr. Eberhard Schlodder (Technische Universitat Berlin) that in both mutants the pheophytin band shift which is observed upon the reduction of Q(A) was centered at 544 nm instead of 547 nm, clearly showing that the D1 protein corresponded to PsbA1 whereas the mutants were supposedly constructed in the psbA(3) gene so that the conclusions in our previous paper were wrong. O-2 evolving mutants have been therefore reconstructed and their analyze shows that they are now correct mutants which are suitable for further studies. Indeed, the D1-H198Q mutation downshifted by approximate to 3 nm the P-680(center dot+)/P-680 difference absorption spectrum in the Soret region and increased the redox potential of the P-680(center dot+)/P-680 couple and the D1-H198A mutation decreased the redox potential of the P-680(center dot+)/P-680 couple all these effects being comparable to those which were observed in Synechocystis sp. PCC 6803 [Diner et al., Biochemistry 40 (2001) 9265-9281 and Merry et al. Biochemistry 37 (1998) 17,439-17,447]. We apologize for having presented wrong data and wrong conclusions in our earlier publication. (C) 2016 Elsevier B.V. All rights reserved.
  • Alain Boussac, A. William Rutherford, Miwa Sugiura
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1847 (6-7) 576 - 586 0005-2728 2015/06 [Peer-reviewed]
     Scientific journal 
    The site for water oxidation in Photosystem II (PSII) goes through five sequential oxidation states (S-0 to S-4) before O-2 is evolved. It consists of a Mn4CaO5-cluster close to a redox-active tyrosine residue (Y-z). Cl is also required for enzyme activity. By using EPR spectroscopy it has been shown that both Ca2+/Sr2+ exchange and Cl-/I- exchange perturb the proportions of centers showing high (S = 5/2) and low spin (S = 1/2) forms of the Systate. The S-3-state was also found to be heterogeneous with: i) a S = 3 form that is detectable by EPR and not sensitive to near-infrared light; and ii) a form that is not EPR visible but in which Mn photochemistry occurs resulting in the formation of a (S2Yz)' split EPR signal upon near-infrared illumination. In Sr/Cl-PSII, the high spin (S = 5/2) form of S-2 shows a marked heterogeneity with a g = 4.3 form generated at low temperature that converts to a relaxed form at g = 4.9 at higher temperatures. The high spin g = 4.9 form can then progress to the EPR detectable form of S-3 at temperatures as low as 180 K whereas the low spin (S = 1/2) S-2-state can only advance to the S-3 state at temperatures >= 235 K. Both of the two S-2 configurations and the two S-3 configurations are each shown to be in equilibrium at >= 235K but not at 198 K. Since both S-2 configurations are formed at 198 K, they likely arise from two specific populations of Si. The existence of heterogeneous populations in Si, Sy and S-3 states may be related to the structural flexibility associated with the positioning of the oxygen O-5 within the cluster highlighted in computational approaches and which has been linked to substrate exchange. These data are discussed in the context of recent in silico studies of the electron transfer pathways between the S-2-state(s) and the S-3-state(s).
  • Boussac A, Rutherford AW, Sugiura M
    Biochimica et biophysica acta 1847 (6-7) 576 - 586 0006-3002 2015/06 [Peer-reviewed]
  • Miwa Sugiura, Makoto Nakamura, Kazumi Koyama, Alain Boussac
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1847 (2) 276 - 285 0005-2728 2015/02 [Peer-reviewed]
     Scientific journal 
    Cytb(559) in Photosystem II is a heterodimeric b-type cytochrome. The subunits, PsbE and PsbF, consist each in a membrane alpha-helix. Roles for Cytb559 remain elusive. In Thermosynechococcus elongatus, taking advantage of the robustness of the PSII variant with PsbA3 as the D1 subunit (WT*3), 4 mutants were designed hoping to get mutants nevertheless the obligatory phototrophy of this cyanobacterium. In two of them, an axial histidine ligand of the haem-iron was substituted for either a methionine, PsbE/H23M, which could be potentially a ligand or for an alanine, PsbE/H23A, which cannot. In the other mutants, PsbE/Y19F and PsbE/T26P, the environment around PsbE/H23 was expected to be modified. From EPR, MALDI-TOF and O-2 evolution activity measurements, the following results were obtained: Whereas the PsbE/H23M and PsbE/H23A mutants assemble only an apo-Cytb(559) the steady-state level of active PSII was comparable to that in WT*3. The lack of the haem or, in PsbE/T26P, conversion of the high-potential into a lower potential form, slowed-down the recovery rate of the O-2 activity after high-light illumination but did not affect the photoinhibition rate. This resulted in the following order for the steady-state level of active PSII centers under high-light conditions: PsbE/H23M approximate to PsbE/H23A << PsbE/Y19F <= PsbE/T26P <= WT*3. These data show i) that the haem has no structural role provided that PsbE and PsbF are present, ii) a lack of correlation between the rate of photoinhibition and the E-m of the haem and iii) that the holo-Cytb(559) favors the recovery of a functional enzyme upon photoinhibition. (C) 2014 Elsevier B.V. All rights reserved.
  • Sugiura M, Nakamura M, Koyama K, Boussac A
    Biochimica et biophysica acta 1847 (2) 276 - 285 0006-3002 2015/02 [Peer-reviewed]
  • Miwa Sugiura, Yui Ozaki, Masato Nakamura, Nicholas Cox, Fabrice Rappaport, Alain Boussac
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1837 (12) 1922 - 1931 0005-2728 2014/12 [Peer-reviewed]
     Scientific journal 
    The main cofactors of Photosystem II (PSII) are borne by the D1 and D2 subunits. In the thermophilic cyanobacterium The rmosynechococcus elongatus, three psbA genes encoding D1 are found in the genome. Among the 344 residues constituting the mature form of D1, there are 21 substitutions between PsbAl and PsbA3, 31 between PsbAl and PsbA2, and 27 between PsbA2 and PsbA3. In a previous study (Sugiura et al., J. Biol. Chem. 287 (2012), 13336-13347) we found that the oxidation kinetics and spectroscopic properties of Tyr(z) were altered in PsbA2-PSII when compared to PsbA(1/3)-PSII. The comparison of the different amino add sequences identified the residues Cys144 and Pro173 found in PsbAl and PsbA3, as being substituted in PsbA2 by Pro144 and Met173, and thus possible candidates accounting for the changes in the geometry and/or the environment of the Tyr(z)/His190 phenol/imidizol motif. Indeed, these amino acids are located upstream of the alpha-helix bearing Tyr(z) and between the two alpha-helices bearing Tyr(z) and its hydrogen-bonded partner, Dl/His190. Here, site-directed mutants of PSII, PsbA3/Pro173Met and PsbA2/Met173Pro, were analyzed using X-and W-band EPR and UV-visible time-resolved absorption spectroscopy. The Pro173Met substitution in PsbA2-PSII versus PsbA3-PSII is shown to be the main structural determinant of the previously described functional differences between PsbA2-PSII and PsbA3-PSII. In PsbA2-PSII and PsbA3/Pro173Met-PSII, we found that the oxidation of Tyr(z) by P-680(+center dot) was specifically slowed during the transition between S-states associated with proton release. We thus propose that the increase of the electrostatic charge of the Mn4CaO5 cluster in the S-2 and S-3 states could weaken the strength of the H-bond interaction between Tyr(z)(center dot) and Dl/His190 in PsbA2 versus PsbA3 and/or induce structural modification(s) of the water molecules network around Tyr(z). (C) 2014 Elsevier B.V. All rights reserved.
  • Sugiura M, Ozaki Y, Nakamura M, Cox N, Rappaport F, Boussac A
    Biochimica et biophysica acta 1837 (12) 1922 - 1931 0006-3002 2014/12 [Peer-reviewed]
  • Miwa Sugiura, Alain Boussac
    RESEARCH ON CHEMICAL INTERMEDIATES 40 (9) 3219 - 3229 0922-6168 2014/11 [Peer-reviewed]
     Scientific journal 
    Cyanobacteria have several psbA genes encoding PsbA, the D1 reaction center protein of the photosystem II (PSII) complex which bears, with PsbD, the D2 protein, most of the cofactors involved in electron-transfer reactions. The thermophilic cyanobacterium Thermosynechococcus elongatus has three psbA genes differently expressed depending on the environmental conditions. Among the 344 residues constituting each of the three possible PsbA variants there are 21 substitutions between PsbA1 and PsbA3, 31 between PsbA1 and PsbA2, and 27 between PsbA2 and PsbA3. In this review, we briefly summarize the changes already identified in the properties of the redox cofactors depending on the D1 variant constituting PSII in T. elongatus.
  • Sugiura M, Boussac A
    Biochimica et biophysica acta 1837 (9) 1427 - 1434 0006-3002 2014/09 [Peer-reviewed]
  • Miwa Sugiura, Chizuko Azami, Kazumi Koyama, A. William Rutherford, Fabrice Rappaport, Alain Boussac
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1837 (1) 139 - 148 0005-2728 2014/01 [Peer-reviewed]
     Scientific journal 
    In Photosystem II (PSII) of the cyanobacterium Thermosynechococcus elongatus, glutamate 130 in the high-light variant of the D1-subunit (PsbA3) was changed to glutamine in a strain lacking the two other genes for D1, psbA(1) and psbA(2). The resulting PSII (PsbA3/Glu130Gln) was compared with those from the "native" high-light (PsbA3-PSII) and low-light (PsbA1-PSII) variants, which differ by 21 amino acid including Glu130Gln. H-bonding from D1-Glu130Gln to the primary electron acceptor, Pheophytin(D1) (Pheo(D1)), is known to affect the E-m, of the Pheo(D1)/Pheo((D1) over bar)center dot couple. The Gln130 mutation here had little effect on water splitting, charge accumulation and photosensitivity but did slow down S(2)Q((A) over bar)center dot charge recombination and up-shift the thermoluminescence while increasing its yield. These changes were consistent with a approximate to -30 mV shift of the Pheo(D1)/Pheo((D1) over bar)center dot E-m, similar to earlier single site-mutation results from other species and double the approximate to -17 mV shift seen for PsbA1-PSII versus PsbA3-PSII. This is attributed to the influence of the other 20 amino-acids that differ in PsbA3. A computational model for simulating S(2)Q((A) over bar)center dot recombination matched the experimental trend: the S(2)Q((A) over bar)center dot recombination rate in PsbA1-PSII differed only slightly from that in PsbA3-PSII, while in Glu130-PsbA3-PSII there was a more pronounced slowdown of the radical pair decay. The simulation predicted a major effect of the Pheo(D1)/Pheo((D1) over bar)center dot potential on O-1(2) yield (similar to 60% in PsbA1-PSII, similar to 20% in PsbA3-PSII and similar to 7% in Gln130-PsbA3-PSII), reflecting differential sensitivities to high light. (C) 2013 Elsevier B.V. All rights reserved.
  • Sugiura M, Azami C, Koyama K, Rutherford AW, Rappaport F, Boussac A
    Biochimica et biophysica acta 1837 (1) 139 - 148 0006-3002 2014/01 [Peer-reviewed]
  • Miwa Sugiura, Kazumi Koyama, Yasufumi Umena, Keisuke Kawakami, Jian-Ren Shen, Nobuo Kamiya, Alain Boussac
    BIOCHEMISTRY 52 (52) 9426 - 9431 0006-2960 2013/12 [Peer-reviewed]
     Scientific journal 
    The electron density map of the 3D crystal of Photosystem II from Thermosynechococcus vulcanus with a 1.9 angstrom resolution (PDB: 3ARC) exhibits, in the two monomers in the asymmetric unit cell, an, until now, unidentified and uninterpreted strong difference in electron density centered at a distance of around 1.5 angstrom from the nitrogen N delta of the imidazole ring of D2-His336. By MALDI-TOF/MS upon tryptic digestion, it is shown that similar to 20-30% of the fragments containing the D2-His336 residue of Photosystem II from both Thermosynechococcus vulcanus and Thermosynechococcus elongatus bear an extra mass of +16 Da. Such an extra mass likely corresponds to an unprecedented post-translational or chemical hydroxyl modification of histidine.
  • Alain Boussac, Kazumi Koyama, Miwa Sugiura
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1827 (10) 1174 - 1182 0005-2728 2013/10 [Peer-reviewed]
     Scientific journal 
    Cyanobacteria have multiple psbA genes encoding PsbA, the D1 reaction center protein of the Photosystem II (PSII) complex. The thermophilic cyanobacterium Thermosynechococcus elongatus has three psbA genes differently expressed depending on the environmental conditions. Among the 344 residues of PsbA, there are 21 substitutions between PsbA1 and PsbA3, 31 between PsbA1 and PsbA2 and 27 between PsbA2 and PsbA3. In this study, we found a new hemoprotein that is expressed when the T. elongatus genome has only the psbA(2) gene for D1. This hemoprotein was found in both the non-membrane proteins and associated to the purified PsbA2-PSII core complex. This protein could be removed by the washing of PSII with Tris-washing or CaCl2-washing. From MALDI-TOF/FOF spectrometry, N-terminal sequencing and MALDI-MS/MS analysis upon tryptic digestion, the new hemoprotein was identified to be the tll0287 gene product with a molecular mass close to 19 kDa. Until now, tll0287 was registered ass gene encoding a hypothetical protein with an unknown function. From the amino acid sequence and the EPR spectrum the 5th and 6th axial ligands of the heme iron are the His145 and likely either the Tyr93, Tyr159 or Tyr165, respectively. From EPR, the heme containing Tll0287 protein associated to PsbA2-PSII corresponds to approximately 25% of the Cytc(550) content whereas, from SDS page analysis, the total amount of Tll0287 with and without the heme seems almost in a stoichiometric amount with PsbA2-PSII. Homologous genes to tll0287 are found in several cyanobacteria. Possible roles for Tll0287 are suggested. (C) 2013 Elsevier B.V. All rights reserved.
  • Michihiro Suga, Thanh-Lan Lai, Miwa Sugiura, Jian-Ren Shen, Alain Boussac
    FEBS LETTERS 587 (19) 3267 - 3272 1873-3468 2013/10 [Peer-reviewed]
     Scientific journal 
    PsbV2 is a c-type cytochrome present in a very low abundance in the thermophilic cyanobacterium Thermosynechococcus elongatus. We purified this cytochrome and solved its crystal structure at a resolution of 1.5 angstrom. The protein existed as a dimer in the crystal, and has an overall structure similar to other c-type cytochromes like Cytc(6) and Cytc(550), for example. However, the 5th and 6th heme iron axial ligands were found to be His51 and Cys101, respectively, in contrast to the more common bis-His or His/Met ligands found in most cytochromes. Although a few other c-type cytochromes were suggested to have this axial coordination, this is the first crystal structure reported for a c-type heme with this unusual His/Cys axial coordination. Previous spectroscopic characterizations of PsbV2 are discussed in relation to its structural properties. (C) 2013 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved.
  • Boussac A, Koyama K, Sugiura M
    Biochimica et biophysica acta 1827 (10) 1174 - 1182 0006-3002 2013/10 [Peer-reviewed]
  • Michihiro Suga, Thanh-Lan Lai, Miwa Sugiura, Jian-Ren Shen, Alain Boussac
    FEBS Letters 587 (19) 3267 - 3272 0014-5793 2013/10 [Peer-reviewed]
     Scientific journal 
    PsbV2 is a c-type cytochrome present in a very low abundance in the thermophilic cyanobacterium Thermosynechococcus elongatus. We purified this cytochrome and solved its crystal structure at a resolution of 1.5 Å. The protein existed as a dimer in the crystal, and has an overall structure similar to other c-type cytochromes like Cytc6 and Cytc550, for example. However, the 5th and 6th heme iron axial ligands were found to be His51 and Cys101, respectively, in contrast to the more common bis-His or His/Met ligands found in most cytochromes. Although a few other c-type cytochromes were suggested to have this axial coordination, this is the first crystal structure reported for a c-type heme with this unusual His/Cys axial coordination. Previous spectroscopic characterizations of PsbV2 are discussed in relation to its structural properties. © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
  • Alain Boussac, Fabrice Rappaport, Klaus Brettel, Miwa Sugiura
    JOURNAL OF PHYSICAL CHEMISTRY B 117 (12) 3308 - 3314 1520-6106 2013/03 [Peer-reviewed]
     Scientific journal 
    Charge recombination in the light-induced radical pair S(n)Tyr(Z)(center dot)Q(A)(-center dot) in Photosystem II (PSII) from Thermosynechococcus elongatus has been studied at cryogenic temperatures by time-resolved EPR for different configurations of PSII that are expected to affect the driving force of the reaction (oxidation states S-0, S-1 or S-2 of the Mn4CaO5 cluster; PsbA1, PsbA2, or PsbA3 as D1 protein). The kinetics were independent of temperature in the studied range from 4.2 to 50 K and were not affected by exchange of H2O for D2O, consistent with single-step electron tunneling over the distance of similar to 32 angstrom without any repopulation through Boltzmann equilibration of intermediates lying higher in energy. In PsbA1-PSII, the charge recombinations in the radical pairs S(n)Tyr(Z)(center dot)Q(A)(-center dot) (k(et) = 3.4 x 10(-3) s(-1) for S-1) were slower than in PsbA3-PSII despite an expected lower driving force owing to a downshifted E-m(Q(A)/Q(A)(-center dot)) in PsbA1-PSII. Conversely, the reaction was slower in the presence of S-2 than in the presence of SI, despite an expected larger driving force due to an upshifted E-m(Tyr(Z)(center dot)/Tyr(Z)) in S-2. These observations indicate that the charge recombination occurs in the Marcus inverted region. Assuming that the driving force of the reaction (-Delta G(0) approximate to 1.2 eV at room temperature for S-1) does not vary strongly with temperature, the data indicate an optimal electron transfer rate (for a hypothetical -Delta G(0) = lambda) substantially faster than would be predicted from extrapolation of room temperature intraprotein ET rates over shorter distances. Possible origins of this deviation are discussed, including a possible enhancement of the electronic coupling of Tyr(Z)(center dot) and Q(A)(-center dot). by aromatic cofactors located in between. Observed similar S(1)Tyrz(center dot)Q(A)(-center dot) charge recombinations in PsbA2-PSII and PsbA3-PSII predict that E-m(Q(A)/Q(A)(-center dot)) in PsbA2-PSII is similar to that in PsbA3-PSII.
  • Yuki Kato, Tadao Shibamoto, Shoichi Yamamoto, Tadashi Watanabe, Naoko Ishida, Miwa Sugiura, Fabrice Rappaport, Alain Boussac
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1817 (11) 1998 - 2004 0005-2728 2012/11 [Peer-reviewed]
     Scientific journal 
    Ca2+ and Cl- ions are essential elements for the oxygen evolution activity of photosystem II (PSII). It has been demonstrated that these ions can be exchanged with Sr2+ and Br-, respectively, and that these ion exchanges modify the kinetics of some electron transfer reactions at the Mn4Ca cluster level (Ishida et at, J. Biol. Chem. 283 (2008) 13330-13340). It has been proposed from thermoluminescence experiments that the kinetic effects arise, at least in part, from a decrease in the free energy level of the Mn4Ca cluster in the S-3 state though some changes on the acceptor side were also observed. Therefore, in the present work, by using thin-layer cell spectroelectrochemistry, the effects of the Ca2+/Sr2+ and Cl-/Br- exchanges on the redox potential of the primary quinone electron acceptor Q(A), E-m(Q(A)/Q(A)(-)), were investigated. Since the previous studies on the Ca2+/Sr2+ and Cl-/Br- exchanges were performed in PsbA3-containing PSII purified from the thermophilic cyanobacterium Thermosynechococcus elongatus, we first investigated the influences of the PsbA1/PsbA3 exchange on E-m(Q(A)/Q(A)(-)). Here we show that i) the E-m(Q(A)/Q(A)(-)) was up-shifted by ca. +38 mV in PsbA3-PSII when compared to PsbA1-PSII and ii) the Ca2+/Sr2+ exchange up-shifted the E-m(Q(A)/Q(A)(-)) by ca. +27 mV, whereas the Cl-/Br- exchange hardly influenced E-m(Q(A)/Q(A)(-)). On the basis of the results of E-m(Q(A)/Q(A)(-)) together with previous thermoluminescence measurements, the ion-exchange effects on the energetics in PSII are discussed. (c) 2012 Elsevier B.V. All rights reserved.
  • Ogami S, Boussac A, Sugiura M
    Biochimica et biophysica acta 1817 (8) 1322 - 1330 0006-3002 2012/10 [Peer-reviewed]
  • Kato Y, Shibamoto T, Yamamoto S, Watanabe T, Ishida N, Sugiura M, Rappaport F, Boussac A
    Biochimica et biophysica acta 1817 (11) 1998 - 2004 0006-3002 2012/09 [Peer-reviewed]
  • Shogo Ogami, Alain Boussac, Miwa Sugiura
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1817 (8) 1322 - 1330 0005-2728 2012/08 [Peer-reviewed]
     Scientific journal 
    The sensitivity to high light conditions of Photosystem II with either PsbA1 (WT*1) or PsbA3 (WT*3) as the D1 protein was studied in whole cells of the thermophilic cyanobacterium Thermosynechococcus elongatus. When the cells are cultivated under high light conditions the following results were found: (i) The O-2 evolution activity decreases faster in WT*1 cells than in WT*3 cells both in the absence and in the presence of lincomycin, a protein synthesis inhibitor; (ii) In WT*1 cells, the rate constant for the decrease of the O-2 evolution activity is comparable in the presence and in the absence of lincomycin; (iii) The D1 content revealed by western blot analysis decays similarly in both WT*1 and WT*3 cells and much slowly than O-2 evolution; (iv) The faster decrease in O-2 evolution in WT*1 than in WT*3 cells correlates with a much faster inhibition of the S-2-state formation: (v) The shape of the WT*1 cells is altered. All these results are in agreement with a photo-inhibition process resulting in the loss of the O-2 activity much faster than the D1 turnover in PsbA1-PSII and likely to a greater production of reactive oxygen species under high light conditions in WT*1 than in WT*3. This latter result is discussed in view of the known effects of the PsbA1 to PsbA3 substitution on the redox properties of the Photosystem II cofactors. The observation that under low light conditions WT*3 cells are able to express the psbA(3) gene, whereas under similar conditions wild type cells are expressing mainly the psbA(1) gene is also discussed. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial. (C) 2012 Elsevier B.V. All rights reserved.
  • Hiroyuki Suzuki, Miwa Sugiura, Takumi Noguchi
    BIOCHEMISTRY 51 (34) 6776 - 6785 0006-2960 2012/08 [Peer-reviewed]
     Scientific journal 
    Water oxidation by plants and cyanobacteria is performed via a light-driven cycle of five intermediates called S states (S-0-S-4) at the water oxidizing center (WOC) in photosystem II (PSII). The information about misses, i.e., the probabilities that the S-state transitions failed to advance, is crucial for detailed analysis of various spectroscopic data in investigations of the water oxidation mechanism. In this study, we have determined the miss probabilities of the individual S-state transitions using light induced Fourier transform infrared (FTIR) difference spectroscopy. The extent of S-state transitions in the WOC upon each saturating flash was monitored by detecting the flow of electrons from the WOC to ferricyanide, an exogenous electron acceptor, using the CN stretching bands of ferricyanide and ferrocyanide. Simulation of the oscillation pattern of the flash-number dependence of the signal amplitude provided the miss probabilities for the S-0 -> S-1, S-1 -> S-2, S-2 -> S-3, and S-3 -> S-0 transitions (alpha(0)-alpha(3), respectively) without any assumption about fitting parameters. The results for PSII preparations from Thermosynechococcus elongatus and spinach showed a general tendency of misses in the order, alpha(0) <= alpha(1) < alpha(2) < alpha(3), indicating that a more oxidized WOC has a higher miss probability. A very similar result observed for the Y-D-less mutant (D2-Y160F) of T. elongatus confirmed that Y-D does not affect the estimated misses. It was further shown that NO3- treatment specifically increased alpha(3), consistent with inactivation of the S-3 state reported previously. These results demonstrate the usefulness of this FTIR method for estimating individual miss probabilities in the S-state cycle in elucidation of the molecular mechanism of photosynthetic water oxidation.
  • Boussac A, Ishida N, Sugiura M, Rappaport F
    Biochimica et biophysica acta 1817 (5) 802 - 810 0006-3002 2012/07 [Peer-reviewed]
  • Alain Boussac, Naoko Ishida, Miwa Sugiura, Fabrice Rappaport
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1817 (5) 802 - 810 0005-2728 2012/05 [Peer-reviewed]
     Scientific journal 
    The active site for water oxidation in Photosystem II (PSII) goes through five sequential oxidation states (S-0 to S-4) before O-2 is evolved. It consists of a Mn4CaO5 cluster and Tyr(Z), a redox-active tyrosine residue. Chloride ions have been known for long time to be required for the function of the enzyme. However, X-ray data have shown that they are located about 7 angstrom away from the Mn4CaO5 cluster, a distance that seems too large to be compatible with a direct involvement of chloride in the water splitting chemistry. We have investigated the role of this anion by substituting I- for Cl- in the cyanobacterium Thermosynechococcus elongatus with either Ca2+ or Sr2+ biosynthetically assembled into the Mn-4 cluster. The electron transfer steps affected by the exchanges were investigated by time-resolved UV-visible absorption spectroscopy, time-resolved EPR at room temperature and low temperature cw-EPR spectroscopy. In both Ca-PSII and Sr-PSII, the Cl-/I- exchange considerably slowed down the two S(3)Tyr(Z)(center dot) -> (S(3)Tyr(Z)(center dot))' -> So reactions in which the fast phase, S(3)Tyr(Z)(center dot) -> (S(3)Tyr(Z)(center dot))', reflects the electrostatically triggered expulsion of one proton from the catalytic center caused by the positive charge near/on Tyr(Z)(center dot) and the slow phase corresponds to the S-0 and O-2 formations and to a second proton release. The t(1/2) for S-0 formation increased from 1.1 ms in Ca/Cl-PSII to approximate to 6 ms in Ca/I-PSII and from 4.8 ms in Sr/Cl-PSII to approximate to 45 ms in Sr/I-PSII. In all cases the Tyr(Z)(center dot) reduction was the limiting step. The kinetic effects are interpreted by a model in which the Ca2+ binding site and the Cl- binding site, although spatially distant, interact. This interaction is likely mediated by the H-bond and/or water molecules network(s) connecting the Cl- and Ca2+ binding sites by which proton release may be channelled. (C) 2012 Elsevier B.V. All rights reserved.
  • Miwa Sugiura, Shogo Ogami, Mai Kusumi, Sun Un, Fabrice Rappaport, Alain Boussac
    JOURNAL OF BIOLOGICAL CHEMISTRY 287 (16) 13336 - 13347 0021-9258 2012/04 [Peer-reviewed]
     Scientific journal 
    The main cofactors that determine the photosystem II (PSII) oxygen evolution activity are borne by the D1 and D2 subunits. In the cyanobacterium Thermosynechococcus elongatus, there are three psbA genes coding for D1. Among the 344 residues constituting D1, there are 21 substitutions between PsbA1 and PsbA3, 31 between PsbA1 and PsbA2, and 27 between PsbA2 and PsbA3. Here, we present the first study of PsbA2-PSII. Using EPR and UV-visible time-resolved absorption spectroscopy, we show that: (i) the time-resolved EPR spectrum of Tyr(Z)(center dot) in the (S(3)Tyr(Z)(center dot))' is slightly modified; (ii) the split EPR signal arising from Tyr(Z)(center dot) in the (S(2)Tyr(Z)(center dot))' state induced by near-infrared illumination at 4.2 K of the S(3)Tyr(Z) state is significantly modified; and (iii) the slow phases of P-680(+). reduction by Tyr(Z) are slowed down from the hundreds of mu s time range to the ms time range, whereas both the S(1)Tyr(Z)(center dot) -> S(2)Tyr(Z) and the S(3)Tyr(Z)(center dot) -> 3 S(0)Tyr(Z) + O-2 transition kinetics remained similar to those in PsbA(1/3)-PSII. These results show that the geometry of the Tyr(Z) phenol and its environment, likely the Tyr-O center dot center dot center dot H center dot center dot center dot N epsilon-His bonding, are modified in PsbA2-PSII when compared with PsbA(1/3)-PSII. They also point to the dynamics of the proton-coupled electron transfer processes associated with the oxidation of Tyr(Z) being affected. From sequence comparison, we propose that the C144P and P173M substitutions in PsbA2-PSII versus PsbA(1/3)-PSII, respectively located upstream of the alpha-helix bearing Tyr(Z) and between the two alpha-helices bearing Tyr(Z) and its hydrogen-bonded partner, His-190, are responsible for these changes.
  • Takumi Noguchi, Hiroyuki Suzuki, Masaya Tsuno, Miwa Sugiura, Chihiro Kato
    BIOCHEMISTRY 51 (15) 3205 - 3214 0006-2960 2012/04 [Peer-reviewed]
     Scientific journal 
    Photosynthetic oxygen evolution by plants and cyanobacteria is performed by water oxidation at the Mn4CaO5 cluster in photosystem II. The reaction is known to proceed via a light-driven cycle of five intermediates called S-i states (i = 0-4). However, the detailed reaction processes during the intermediate transitions remain unresolved. In this study, we have directly detected the proton and protein dynamics during the oxygen-evolving reactions using time-resolved infrared spectroscopy. The time courses of the absorption changes at 1400 and 2500 cm(-1), which represent the reactions and/or interaction changes of carboxylate groups and the changes in proton polarizability of strong hydrogen bonds, respectively, were monitored upon flash illumination. The results provided experimental evidence that during the S-3 -> S-0 transition, drastic proton rearrangement, most likely reflecting the release of a proton from the catalytic site, takes place to form a transient state before the oxidation of the Mn4CaO5 cluster that leads to O-2 formation. Early proton movement was also detected during the S-2 -> S-3 transition. These observations reveal the common mechanism in which proton release facilitates the transfer of an electron from the Mn4CaO5 cluster in the S-2 and S-3 states that already accumulate oxidizing equivalents. In addition, relatively slow rearrangement of carboxylate groups was detected in the S-0 -> S-1 transition, which could contribute to the stabilization of the S-1 state. This study demonstrates that time-resolved infrared detection is a powerful method for elucidating the detailed molecular mechanism of photosynthetic oxygen evolution by pursuing the reactions of substrate and amino acid residues during the S-state transitions.
  • Keisuke Saito, Toyokazu Ishida, Miwa Sugiura, Keisuke Kawakami, Yasufumi Umena, Nobuo Kamiya, Jian-Ren Shen, Hiroshi Ishikita
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 133 (36) 14379 - 14388 0002-7863 2011/09 [Peer-reviewed]
     Scientific journal 
    The reaction center chlorophylls a (Chla) of photosystem II (PSII) are composed of six Chla molecules including the special pair Chla P-D1/P-D2 harbored by the D1/D2 heterodimer. They serve as the ultimate electron abstractors for water oxidation in the oxygen-evolving Mn4CaO5 cluster. Using the PSII crystal structure analyzed at 1.9 angstrom resolution, the redox potentials of P-D1/center dot P-D2 for one-electron oxidation (E-m) were calculated by considering all PSII subunits and the protonation pattern of all titratable residues. The Em(Chla) values were calculated to be 1015-1132 mV for P-D1 and 1141-1201 mV for P-D2, depending on the protonation state of the Mn4CaO5 cluster. The results showed that Em(P-D1) was lower than E-m(P-D2) P-D2 favoring localization of the charge of the cationic state more on P-D1. The P-D1(center dot+)/P-D2(center dot+) charge ratio determined by the large-scale QM/MM calculations with the explicit PS II protein environment yielded a P-D1(center dot+)/P-D2(center dot+) ratio of similar to 80/similar to 20, which was found to be due to the asymmetry in electrostatic characters of several conserved D1/D2 residue pairs that cause the E-m(P-D1)/E-m(P-D2) difference, e.g., Dl -Asn181/D2-Argl 80, D1-Asn298/D2-Arg294, D1-Asp61/D2-His61, D1-Glu189/D2-Phe188, and D1-Asp170/D2-Phe169. The larger P-D1(center dot+) population than P-D2(center dot+) appears to be an inevitable fate of the intact PSII that possesses water oxidation activity.
  • Sedoud, A, Cox, N, Sugiura, M, Lubitz, W, Boussac, A, Rutherford, W.A
    Biochemistry 50 6012 - 6021 2011/08 [Peer-reviewed]
  • Fabrice Rappaport, Naoko Ishida, Miwa Sugiura, Alain Boussac
    ENERGY & ENVIRONMENTAL SCIENCE 4 (7) 2520 - 2524 1754-5692 2011/07 [Peer-reviewed]
     Scientific journal 
    The role of Ca2+ in the Photosystem II water oxidation mechanism has been investigated in the higher redox states of the enzyme. The involvement of Ca2+ in structuring the environment of the tyrosine Y-Z in the S-3 state has been investigated by studying the effect of a Ca/Sr exchange by pulse-EPR spectroscopy. It is shown that Ca and Yz are involved in a common hydrogen bond network in S-3. The comparison of the temperature dependence of the rate of the water oxidation reaction shows that the slowdown of the S3YZ center dot -> S-0 transition in Sr-PSII mainly arises from a decrease of the entropic part of the Delta G(#) of the reaction. This suggests that Ca/Sr exchange perturbs the distribution of the conformational microstates and thereby hinders the overall water splitting process.
  • Rappaport, F, Ishida, N, Sugiura, M, Boussac, A
    Energy & Environmental Science in press (321) 355 - 360 2011/07 [Peer-reviewed]
  • Masahiro Ando, Miwa Sugiura, Hidenori Hayashi, Hiro-o Hamaguchi
    APPLIED SPECTROSCOPY 65 (5) 488 - 492 0003-7028 2011/05 [Peer-reviewed]
     Scientific journal 
    We have constructed a 1064 nm deep near-infrared (NIR) excited multichannel Raman microspectrometer using an InP/InGaAsP multichannel detector. This microspectrometer achieves high sensitivity suitable for in vivo measurements of single living cells with lateral resolution of 0.7 mu m and depth resolution of 3.1 mu m. It has been applied to the structural analysis of living cyanobacterial cells, well-known model organisms for photosynthesis research, which are too photolabile to be measured with visible laser excitation. High signal-to-noise ratio (SIN) Raman spectra have been obtained from carotenoid, chlorophyll a, and phycocyanin in a single living cyanobacterial cell with no appreciable interference from autofluorescence or photodamage. Sub-micrometer mapping of Raman intensities provides clear distribution images of the three pigments inside the cell.
  • Nicholas Cox, Leonid Rapatskiy, Ji-Hu Su, Dimitrios A. Pantazis, Miwa Sugiura, Leonid Kulik, Pierre Dorlet, A. William Rutherford, Frank Neese, Alain Boussac, Wolfgang Lubitz, Johannes Messinger
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 133 (10) 3635 - 3648 0002-7863 2011/03 [Peer-reviewed]
     Scientific journal 
    The electronic structures of the native Mn4OxCa cluster and the biosynthetically substituted Mn4OxSr cluster of the oxygen evolving complex (OEC) of photosystem II (PSII) core complexes isolated from Thermosynechococcus elongatus, poised in the S-2 state, were studied by X- and Q-band CW-EPR and by pulsed Q-band Mn-55-ENDOR spectroscopy. Both wild type and tyrosine D less mutants grown photoautotrophically in either CaCl2 or SrCl2 containing media were measured. The obtained CW-EPR spectra of the S-2 state displayed the characteristic, clearly noticeable differences in the hyperfine pattern of the multiline EPR signal [Boussac et al. J. Biol. Chem. 2004, 279, 22809-22819]. In sharp contrast, the manganese (Mn-55) ENDOR spectra of the Ca and Sr forms of the OEC were remarkably similar. Multifrequency simulations of the X- and Q-band CW-EPR and Mn-55-pulsed ENDOR spectra using the Spin Hamiltonian formalism were performed to investigate this surprising result. It is shown that (i) all four manganese ions contribute to the Mn-55-ENDOR spectra; (ii) only small changes are seen in the fitted isotropic hyperfine values for the Ca2+ and Sr2+ containing OEC, suggesting that there is no change in the overall spin distribution (electronic coupling scheme) upon Ca2+/Sr2+ substitution; (iii) the changes in the CW-EPR hyperfine pattern can be explained by a small decrease in the anisotropy of at least two hyperfine tensors. It is proposed that modifications at the Ca2+ site may modulate the fine structure tensor of the Mn-III ion. DFT calculations support the above conclusions. Our data analysis also provides strong support for the notion that in the S-2 state the coordination of the Mn-III ion is square-pyramidal (5-coordinate) or octahedral (6-coordinate) with tetragonal elongation. In addition, it is shown that only one of the currently published OEC models, the Siegbahn structure [Siegbahn, P. E. M. Acc. Chem. Res. 2009, 42, 1871-1880, Pantazis, D. A. et al. Phys. Chem. Chem. Phys. 2009, 11, 6788-6798], is consistent with all data presented here. These results provide important information for the structure of the OEC and the water-splitting mechanism. In particular, the 5-coordinate Mn-III is a potential site for substrate 'water' (H2O, OH-) binding. Its location within the cuboidal structural unit, as opposed to the external 'dangler' position, may have important consequences for the mechanism of O-O bond formation.
  • Alain Boussac, Miwa Sugiura, Fabrice Rappaport
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1807 (1) 119 - 129 0005-2728 2011/01 [Peer-reviewed]
     Scientific journal 
    The main cofactors involved in Photosystem II (PSII) oxygen evolution activity are borne by two proteins, D1 (PsbA) and D2 (PsbD). In Thermosynechococcus elongatus, a thermophilic cyanobacterium, the D1 protein is predominantly encoded by either the psbA(1) or the psbA(3) gene, the expression of which depends on the environmental conditions. In this work, the Q(B) site properties in PsbA1-PSII and PsbA3-PSII were probed through the binding properties of DCMU, a urea-type herbicide, and bromoxynil, a phenolic-type herbicide. This was done by using helium temperature EPR spectroscopy and by monitoring the time-resolved changes of the redox state of Q(A) by absorption spectroscopy in PSII purified from a His(6)-tagged WT strain expressing PsbA1 or from a His(6)-tagged strain in which both the psbA(1) and psbA(2) genes have been deleted and which therefore only express PsbA3. It is shown that, in both PsbA1-PSII and PsbA3-PSII, bromoxynil does not bind to PSII when Q(B) is in its semiquinone state which indicates a much lower affinity for PSII when Q(A) is in its semiquinone state than when it is in its oxidized state. This is consistent with the midpoint potential of Q(A)(center dot-)/Q(A) being more negative in the presence of bromoxynil than in its absence [Krieger-Liszkay and Rutherford, Biochemistry 37 (1998) 17339-17344]. The addition in the dark of DCMU, but not that of bromoxynil, to PSII with a secondary electron acceptor in the Q(B)(center dot-) state induces the oxidation of the non-heme iron in a fraction of PsbA3-PSII but not in PsbA1-PSII. These results are explained as follows: i) bromoxynil has a lower affinity for PSII with the non-heme iron oxidized than DCMU therefore, ii) the midpoint potential of the Fe(II)/Fe(III) couple is lower with DCMU bound than with bromoxynil bound in PsbA3-PSII; and iii) the midpoint potential of the Fe(II)/Fe(III) couple is higher in PsbA1-PSII than in PsbA3-PSII. The observation of DCMU-induced oxidation of the non-heme iron leads us to propose that Q(2), an electron acceptor identified by Joliot and Joliot [FEBS Lett 134 (1981) 155-158], is the non-heme iron. (C) 2010 Elsevier B.V. All rights reserved.
  • Miwa Sugiura, Eri Iwai, Hidenori Hayashi, Alain Boussac
    JOURNAL OF BIOLOGICAL CHEMISTRY 285 (39) 30008 - 30018 0021-9258 2010/09 [Peer-reviewed]
     Scientific journal 
    The main cofactors involved in the oxygen evolution activity of Photosystem II (PSII) are located in two proteins, D1 (PsbA) and D2 (PsbD). In Thermosynechococcus elongatus, a thermophilic cyanobacterium, the D1 protein is encoded by either the psbA(1) or the psbA(3) gene, the expression of which is dependent on environmental conditions. It has been shown that the energetic properties of the PsbA1-PSII and those of the PsbA3-PSII differ significantly (Sugiura, M., Kato, Y., Takahashi, R., Suzuki, H., Watanabe, T., Noguchi, T., Rappaport, F., and Boussac, A. (2010) Biochim. Biophys. Acta 1797, 1491-1499). In this work the structural stability of PSII upon a PsbA1/PsbA3 exchange was investigated. Two deletion mutants lacking another PSII subunit, PsbJ, were constructed in strains expressing either PsbA1 or PsbA3. The PsbJ subunit is a 4-kDa transmembrane polypeptide that is surrounded by D1 (i.e. PsbA1), PsbK, and cytochrome b(559) (Cyt b(559)) in existing three-dimensional models. It is shown that the structural properties of the PsbA3/Delta PsbJ-PSII are not significantly affected. The polypeptide contents, the Cyt b(559) properties, and the proportion of PSII dimer were similar to those found for PsbA3-PSII. In contrast, in PsbA1/Delta PsbJ-PSII the stability of the dimer is greatly diminished, the EPR properties of the Cyt b(559) likely indicates a decrease in its redox potential, and many other PSII subunits are lacking. These results shows that the 21-amino acid substitutions between PsbA1 and PsbA3, which appear to be mainly conservative, must include side chains that are involved in a network of interactions between PsbA and the other PSII subunits.
  • Miwa Sugiura, Sayo Harada, Takashi Manabe, Hidenori Hayashi, Yasuhiro Kashino, Alain Boussac
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1797 (8) 1546 - 1554 0005-2728 2010/08 [Peer-reviewed]
     Scientific journal 
    A deletion mutant that lacks the Psb30 protein, one of the small subunits of Photosystem II, was constructed in a Thermosynechococcus elongatus strain in which the D1 protein is expressed from the psbA(3) gene (WT*). The Delta Psb30 mutant appears more susceptible to photodamage, has a cytochrome b(559) that is converted into the low potential form, and probably also lacks the PsbY subunit. In the presence of an inhibitor of protein synthesis, the Delta Psb30 lost more rapidly the water oxidation function than the WT* under the high light conditions. These results suggest that Psb30 contributes to structurally and functionally stabilise the Photosystem II complex in preventing the conversion of cytochrome b(559) into the low potential form. Structural reasons for such effects are discussed. (C) 2010 Elsevier B.V. All rights reserved.
  • Miwa Sugiura, Yuki Kato, Ryouta Takahashi, Hiroyuki Suzuki, Tadashi Watanabe, Takumi Noguchi, Fabrice Rappaport, Alain Boussac
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1797 (8) 1491 - 1499 0005-2728 2010/08 [Peer-reviewed]
     Scientific journal 
    The main cofactors involved in the function of Photosystem II (PSII) are borne by the D1 and D2 proteins. In some cyanobacteria, the D1 protein is encoded by different psbA genes. In Thermosynechococcus elongatus the amino acid sequence deduced from the psbA(3) gene compared to that deduced from the psbA(1) gene points a difference of 21 residues. In this work. PSII isolated from a wild type T. elongatus strain expressing PsbA(1) or from a strain in which both the psbA(1) and psbA(2) genes have been deleted were studied by a range of spectroscopies in the absence or the presence of either a urea type herbicide, DCMU, or a phenolic type herbicide, bromoxynil. Spectro-electrochemical measurements show that the redox potential of Pheo(D1) is increased by 17 mV from -522 mV in PsbA1-PSII to -505 mV in PsbA3-PSII. This increase is about half that found upon the D1-Q130E single site directed mutagenesis in Synechocystis PCC 6803. This suggests that the effects of the D1-Q130E substitution are, at least partly, compensated for by some of the additional amino-acid changes associated with the PsbA3 for PsbA1 substitution. The thermoluminescence from the S(2)QA(-center dot). charge recombination and the C equivalent to N vibrational modes of bromoxynil detected in the non-heme iron FTIR difference spectra support two binding sites (or one site with two conformations) for bromoxynil in PsbA3-PSII instead of one in PsbA1-PSII which suggests differences in the Q(B) pocket. The temperature dependences of the S(2)Q(A)(-center dot) charge recombination show that the strength of the H-bond to Pheo(D1) is not the only functionally relevant difference between the PsbA3-PSII and PsbA1-PSII and that the environment of Q(A) (and, as a consequence, its redox potential) is modified as well. The electron transfer rate between P-680(+center dot) and Y-z is found faster in PsbA3 than in PsbA1 which suggests that the redox potential of the P-680/P-680(+center dot) couple (and hence that of P-1(680)center dot/P-680(+)center dot) is tuned as well when shifting from PsbAl to PsbA3. In addition to D1-Q130E, the non-conservative amongst the 21 amino acid substitutions, D1-S270A and D1-S153A, are proposed to be involved in some of the observed changes. (C) 2010 Elsevier B.V. All rights reserved.
  • Masahiro Ando, Miwa Sugiura, Hidenori Hayashi, Hiro-O Hamaguchi
    AIP Conference Proceedings 1267 798 - 799 0094-243X 2010 [Peer-reviewed]
     International conference proceedings
  • Michele Vittadello, Maxim Y. Gorbunov, Daniel T. Mastrogiovanni, Leszek S. Wielunski, Eric L. Garfunkel, Fernando Guerrero, Diana Kirilovsky, Miwa Sugiura, A. William Rutherford, Ahmad Safari, Paul G. Falkowski
    CHEMSUSCHEM 3 (4) 471 - 475 1864-5631 2010 [Peer-reviewed]
     Scientific journal 
    By using a nondestructive, ultrasensitive, fluorescence kinetic technique, we measure in situ the photochemical energy conversion efficiency and electron transfer kinetics on the acceptor side of histidine-tagged photosystem II core complexes tethered to gold surfaces. Atomic force microscopy images coupled with Rutherford backscattering spectroscopy measurements further allow us to assess the quality, number of layers, and surface density of the reaction center films. Based on these measurements, we calculate that the theoretical photo-electronic current density available for an ideal monolayer of core complexes is 43 mu A cm(-2) at a photon flux density of 2000 mu mol quanta m(-2) s(-1) between 365 and 750 nm. While this current density is approximately two orders of magnitude lower than the best organic photovoltaic cells (for an equivalent area), it provides an indication for future improvement strategies. The efficiency could be improved by increasing the optical cross section, by tuning the electron transfer physics between the core complexes and the metal surface, and by developing a multilayer structure, thereby making biomimetic photoelectron devices for hydrogen generation and chemical sensing more viable.
  • Yuichi Shibuya, Ryouta Takahashi, Tatsunori Okubo, Hiroyuki Suzuki, Miwa Sugiura, Takumi Noguchi
    BIOCHEMISTRY 49 (3) 493 - 501 0006-2960 2010/01 [Peer-reviewed]
     Scientific journal 
    The primary electron acceptor pheophytin (PheO(D1)) plays a crucial role in regulation of forward and backward electron transfer in photosystem II (PSII). It is known that some cyanobacteria control the Pheo(D1) potential in high-light acclimation by exchanging the DI proteins from different copies of the psbA genes. To clarify file mechanism of the potential control of PheODh we studied the hydrogen bond interactions of Pheo(D1) in the neutral and anionic States using light-induced Fourier transform infrared (FTIR) difference spectroscopy. FTIR difference spectra of Pheol:)l upon its photoreduction were obtained using three different PSII preparations, PSII core complexes from Thermosynehococcus elongatus possessing PsbA1 as a D1 subunit (PSII-PsbA1), those with PsbA3 (PSII-PsbA3), and PSII membranes from spinach. The DI-Gln130 side chain, which is hydrogen bonded to the 13(1)-keto C=O group of Pheo(D1) PSII membranes from spinach. The D1-Gln130 in PSII-PsbA3 and spinach PSIL The spectrum of PSII-PsbA1 exhibited 131-keto C=O bands at 1682 and 1605 cm(-1) in neutral Pheol), and its anion, respectively, while the corresponding bands were observed at frequencies lower by 1-3 and 18-19cm(-1), respectively, in the latter two preparations. This larger frequency shift in PhcoD(1)(-) than Plleol), by the change of the hydrogen bond donor Was well reproduced by density functional theory (DFT) calculations for the Pheo models hydrogen bonded with acetamide and acetic acid. The DFT calculations also exhibited a higher redox potential for Pheo reduction in the model with acetic acid than that with acetamide, consistent with previous observations for the D1-Gln130GIu mutant of Synechocystis. It is thus concluded that a stronger hydrogen bond effect oil the Pheo(-) anion than the neutral Pheo causes the shift in the redox potential, which IS utilized In the photoprotection mechanism of PSII.
  • Joseph L. Hughes, Nicholas Cox, A. William Rutherford, Elmars Krausz, Thanh-Lan Lai, Alain Boussac, Miwa Sugiura
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1797 (1) 11 - 19 0005-2728 2010/01 [Peer-reviewed]
     Scientific journal 
    In Photosystem II (PSII) from Thermosynechococcus elongatus, high-light intensity growth conditions induce the preferential expression of the psbA(3) gene over the psbA(1) gene. These genes encode for the D1 protein variants labeled D1:3 and D1:1, respectively. We have compared steady state absorption and photo-induced difference spectra at <10 K of PSII containing either D1:1 or D1:3. The following differences were observed. (i) The pheophytin Q(x) band was red-shifted in D1:3 (547.3 nm) compared to D1:1 (544.3 nm). (ii) The electrochromism on the PheO(D1) Q(x) band induced by Q(A)(-) (the C550 shift) was more asymmetric in D1:3. (iii) The two variants differed in their responses to excitation with far red (704 nm) light When green light was used there was little difference between the two variants. With far red light the stable (t(1/2)>50 ms) W yield was similar to 95% in D1:3, and similar to 60% in D1:1, relative to green light excitation. (iv) For the D1:1 variant, the quantum efficiency of photo-induced oxidation of side-pathway donors was lower. These effects can be correlated with amino acid changes between the two D1 variants. The effects on the pheophytin Q(x) band can be attributed to the hydrogen bond from Glu130 in D1:3 to the 13(1)-keto of PheOD1, which is absent for Gln130 in D1:1. The reduced yield with red light in the D1:1 variant could be associated with either the Glu130Gln change, and/or the four changes near the binding site of P(D1), in particular Ser153Ala. Photoinduced Q(A)(-) formation with far red light is assigned to the direct optical excitation of a weakly absorbing charge transfer state of the reaction centre. We suggest that this state is blue-shifted in the D1:1 variant A reduced efficiency for the oxidation of side-pathway donors in the D1:I variant could be explained by a variation in the location and/or redox potential of P(+). (C) 2009 Elsevier B.V. All rights reserved.
  • Tadao Shibamoto, Yuki Kato, Miwa Sugiura, Tadashi Watanabe
    BIOCHEMISTRY 48 (45) 10682 - 10684 0006-2960 2009/11 [Invited]
     Scientific journal 
    The redox potential of the primary plastoquinone electron acceptor Q(A), E-m(Q(A)/Q(A)(-)), in an oxygen-evolging photosystem (PS) 11 complex from a thermophilic cyanobacterium Thermosynechococcus elongatus was determined to be - 140 +/- 2 mV vs. SHE by thin-layer cell spectroclectrochemistry for the first time. The E-m(Q(A)/Q(A)(-)) value obtained here together with the recently determined redox potential of pheophytin (Phe) a [Kato et at. (2009) Proc. Natl. Acad. Sci. U.S.A. 106, 17365-17370] yields -330 to -370 mV for the free energy change by electron transfer from Phe a(-) to Q(A) and provides a renewed picture for the energetics oil the electron acceptor side in PS II.
  • Yuki Kato, Miwa Sugiura, Akinori Oda, Tadashi Watanabe
    PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 106 (41) 17365 - 17370 0027-8424 2009/10 [Peer-reviewed]
     Scientific journal 
    Thin-layer cell spectroelectrochemistry, featuring rigorous potential control and rapid redox equilibration within the cell, was used to measure the redox potential E(m)(Phe a/Phe a(-)) of pheophytin (Phe) a, the primary electron acceptor in an oxygen-evolving photosystem (PS) II core complex from a thermophilic cyanobacterium Thermosynechococcus elongatus. Interferences from dissolved O(2) and water reductions were minimized by airtight sealing of the sample cell added with dithionite and mercury plating on the gold minigrid working electrode surface, respectively. The result obtained at a physiological pH of 6.5 was E(m)( Phe a/Phe a(-)) = -505 +/- 6 mV vs. SHE, which is by approximate to 100 mV more positive than the values measured approximate to 30 years ago at nonphysiological pH and widely accepted thereafter in the field of photosynthesis research. Using the P680* - Phe a free energy difference, as estimated from kinetic analyses by previous authors, the present result would locate the E(m)(P680/P680(+)) value, which is one of the key parameters but still resists direct measurements, at approximately +1,210 mV. In view of these pieces of information, a renewed diagram is proposed for the energetics in PS II.
  • Ryouta Takahashi, Alain Boussac, Miwa Sugiura, Takumi Noguchi
    BIOCHEMISTRY 48 (38) 8994 - 9001 0006-2960 2009/09 [Peer-reviewed]
     Scientific journal 
    The non-heme iron is located between the quinone electron acceptors, Q(A) and Q(B), in photosystem II (PSII), and together with its bicarbonate ligand, it regulates the electron and proton transfer reactions of quinone acceptors. In this study, we have investigated the structural coupling of a nearby Tyr residue with the non-heme iron center using Fourier transform infrared (FTIR) spectroscopy. Light-induced FC(2+)/Fe(3+) FTIR difference spectra of PSII core complexes from unlabeled and [4-(13)C]Tyr-labeled Thermosynechococcus elongatus revealed that the CO stretching (nu CO) bands of a Tyr side chain are located at 1253 and 1241 cm(-1) in the Fe(2+) and Fe(3+) states, respectively. Upon deuteration, both nu CO bands were upshifted by 11-12 cm(-1). Taking into account the criteria for determining the hydrogen bond structure of a Tyr side chain from infrared bands reported previously [Takahashi, R., and Noguchi, T. (2007) J. Phys. Chem. B 111, 13833-13844] and the results of DFT calculations of model complexes of p-cresol hydrogen-bonded with bicarbonate, we interpreted the observed nu CO bands and their deuteration effects as indicating that one Tyr side chain with a hydrogen bond donor-acceptor form is strongly coupled to the non-heme iron. From the X-ray structures of PSII core complexes, it is proposed that either D1-Y246 or D2-Y244 provides a hydrogen bond to the oxygen of the bicarbonate ligand but the other Tyr does not directly interact with bicarbonate. The Tyr residue coupled to the non-heme iron may play a key role in the regulatory function of the iron-bicarbonate center by stabilizing the bicarbonate ligand and forming a rigid hydrogen bond network around the non-heme ion.
  • Miwa Sugiura, Fabrice Rappaport, Warwick Hillier, Pierre Dorlet, Yohei Ohno, Hidenori Hayashi, Alain Boussac
    BIOCHEMISTRY 48 (33) 7856 - 7866 0006-2960 2009/08 [Peer-reviewed]
     Scientific journal 
    Oxygen evolution by Photosystem II (PSII) is catalyzed by a Mn4Ca cluster. Thus far, from the crystallographic three-dimensional (3D) structures, seven amino, acid residues have been identified as possible ligands of the Mn4Ca cluster. Among them, there is only one histidine, His332, which belongs to the D1 polypeptide. The relationships of the D1-His332 amino acid with kinetics and thermodynamic properties of the Mn4Ca cluster in the S-2- and S-3-states of the catalytic cycle were investigated in purified PSII from Thermosynechococcus elongatus. This was done by examining site-directed D1-His332Gln and D1-His332Ser mutants by a variety of spectroscopic techniques such as time-resolved UV-visible absorption change spectroscopy, cw- and pulse-EPR, thermoluminescence, and measurement of substrate water exchange. Both mutants grew photo-autotrophically and active PSII could be purified. On the basis of the parameters assessed in this work, the D1-His332(Gln, Ser) mutations had no effect in the S-2-state. Electron spin-echo envelope modulation (ESEEM) spectroscopy also showed that possible interactions between the nuclear spin of the nitrogen(s) of D1-His332 with the electronic spin S = 1/2 of the Mn4Ca cluster in the S-2-state were not detectable and that the D1-His332Ser mutation did not affect the detected hyperfine couplings. In contrast, the following changes were observed in the S-3-state of the D1-His332 mutants: (1) The redox potential of the S-3/S-2 couple was slightly increased by <= 20 meV, (2) The S-3-EPR spectrum was slightly modified, (3) The D1-His332Gln mutation resulted in it similar to 3 fold decrease of the slow (tightly bound) exchange rate and it similar to 2 fold increase of the fast exchange rate of the water substrate molecules. All these results suggest that the D1-His332 would be more involved in S-3 than in S-2. This could be one element of the conformational changes put forward in the S-2 to S-3 transition.
  • Hiroyuki Suzuki, Miwa Sugiura, Takumi Noguchi
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 131 (22) 7849 - 7857 0002-7863 2009/06 [Peer-reviewed]
     Scientific journal 
    In photosynthetic water oxidation performed in the water oxidizing center (WOC) of photosystem II (PSII), two water molecules are converted into one oxygen molecule and four protons through a light-driven cycle of intermediates called S states (S-0-S-4). To understand the molecular mechanism of water oxidation and the chemical nature of substrate intermediates, it is essential to determine the stoichiometry of proton release from substrate water at individual S-state transitions. In this study, we have monitored proton release during water oxidation by means of isotope-edited Fourier transform infrared (FTIR) spectroscopy. FTIR difference spectra upon successive flash illumination were measured using PSII core complexes from a thermophilic cyanobacterium Thermosynechococcus elongatus, which were suspended in a high concentration (200 mM) Mes buffer at pH 6.0. The spectra involved, in addition to protein bands, the bands of the Mes buffer that trapped virtually all protons from the WOC. Mes-only signals were extracted by subtracting the spectra measured in deuterated-Mes (Mes-d(12)). The flash-number dependence of the intensity increase of the isotope-edited Mes signal showed a clear period-four oscillation. By simulating the oscillation with different assumptions about miss factors, the proton release pattern was estimated to be 0.8-1.0:0.2-0.3:0.9-1.2:1.5-1.6 for the S-0 -> S-1 -> S-2 -> S-3 -> S-0 transitions. The effect of H/D exchange on the COOH region of proteins in FTIR difference spectra of the S-state cycle showed that protonation/deprotonation of carboxylic groups contributed little to the observed proton release pattern. Together with the present and previous FTIR results suggesting no involvement of also His and Cys side groups, it was concluded that proton release from substrate water takes place with a 1:01:2 stoichiometry, which is perturbed by partial protonation/deprotonation of side groups probably of Arg, Lys, or Tyr located nearby the WOC.
  • Alain Boussac, Miwa Sugiura, A. William Rutherford, Pierre Dorlet
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 131 (14) 5050 - + 0002-7863 2009/04 [Peer-reviewed]
     Scientific journal 
    Despite crystallographic structures now available and intensive work in the past decades, little is known about the higher redox states of the catalytic cycle of Photosystem II, the enzyme responsible for the presence of O-2 on Earth and at the beginning of the process that has produced both the biomass and the fossil fuels. In one of the highest oxidation states, the S-3-state, only signals at S-values higher than 4 have been detected so far at the X-band. In this work, we report for the first time the complete X-band EPR spectrum for the S-3-state of Photosystem II. Simutations show that, for a spin state S = 1, as was previously suggested for S-3, it is not possible to account for all the features observed. A satisfactory simulated spectrum was obtained for a spin state S = 3 with zero-field splitting parameters D = 0.175 cm(-1) and E/D = 0.275. The detection of the full. EPR signal for S-3 opens the door for new investigations and a better understanding of the catalytic cycle of Photosystern II.
  • Fabrice Rappaport, Alain Boussac, Dee Ann Force, Jeffrey Peloquin, Marcin Brynda, Miwa Sugiura, Sun Un, R. David Britt, Bruce A. Diner
    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY 131 (12) 4425 - 4433 0002-7863 2009/04 [Peer-reviewed]
     Scientific journal 
    The catalytic cycle of numerous enzymes involves the coupling between proton transfer and electron transfer. Yet, the understanding of this coordinated transfer in biological systems remains limited, likely because its characterization relies on the controlled but experimentally challenging modifications of the free energy changes associated with either the electron or proton transfer. We have performed such a study here in Photosystem II. The driving force for electron transfer from Tyr(z) to P(680)(*+) has been decreased by similar to 80 meV by mutating the axial ligand of P(680), and that for proton transfer upon oxidation of Tyr(z) by substituting a 3-fluorotyrosine (3F-Tyr(z)) for Tyrz. In Mn-depleted Photosystem 11, the dependence upon pH of the oxidation rates of Tyrz and 3F-Tyrz were found to be similar. However, in the pH range where the phenolic hydroxyl of Tyrz is involved in a H-bond with a proton acceptor, the activation energy of the oxidation of 3F-Tyrz is decreased by 110 meV, a value which correlates with the in vitro finding of a 90 meV stabilization energy to the phenolate form of 3F-Tyr when compared to Tyr (Seyedsayamdost et al. J. Am. Chem. Soc. 2006, 128,1569-1579). Thus, when the phenol of Y(z) acts as a H-bond donor, its oxidation by P680(*+) is controlled by its prior deprotonation. This contrasts with the situation prevailing at lower pH, where the proton acceptor is protonated and therefore unavailable, in which the oxidation-induced proton transfer from the phenolic hydroxyl of Tyrz has been proposed to occur concertedly with the electron transfer to P680(*+). This suggests a switch between a concerted proton/electron transfer at pHs < 7.5 to a sequential one at pHs > 7.5 and illustrates the roles of the H-bond and of the likely salt-bridge existing between the phenolate and the nearby proton acceptor in determining the coupling between proton and electron transfer.
  • Malwina Szczepaniak, Miwa Sugiura, Alfred R. Holzwarth
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1777 (12) 1510 - 1517 0005-2728 2008/12 [Peer-reviewed]
     Scientific journal 
    Redox-active tyrosine (Tyr) D is indirectly involved in controlling the primary electron transfer in PSII The presence of the oxidized TyrD renders P680(+) more oxidizing by localizing the charge more on P(D1) and thus facilitates trapping of the excitation energy in PSII. We also conclude that the mechanism of the primary charge separation and stabilization is altered upon Q(A) reduction. (C) 2008 Elsevier B.V. All rights reserved.
  • J. W. Murray, K. Maghlaoui, J. Kargul, M. Sugiura, J. Barber
    PHOTOSYNTHESIS RESEARCH 98 (1-3) 523 - 527 0166-8595 2008/10 [Peer-reviewed]
     Scientific journal 
    In order to investigate oxygen binding and hydrophobic cavities in photosystem II (PSII), we have introduced xenon under pressure into crystals of PSII isolated from Thermosynechococcus elongatus and used X-ray anomalous diffraction analyses to identify the xenon sites in the complex. Under the conditions employed, 25 Xe-binding sites were identified in each monomer of the dimeric PSII complex. The majority of these were distributed within the membrane spanning portion of the complex with no obvious correlation with the previously proposed oxygen channels. One binding site was located close to the haem of cytochrome b559 in a position analogous to a Xe-binding site of myoglobin. The only Xe-binding site not associated with the intrinsic subunits of PSII was within the hydrophobic core of the PsbO protein.
  • Hiroyuki Suzuki, Miwa Sugiura, Takumi Noguchi
    BIOCHEMISTRY 47 (42) 11024 - 11030 0006-2960 2008/10 [Peer-reviewed]
     Scientific journal 
    Photosynthetic water oxidation takes place in the water-oxidizing center (WOC) of photosystem II (PSII). To clarify the mechanism of water oxidation, detecting water molecules in the WOC and monitoring their reactions at the molecular level are essential. In this study, we have for the first time detected the DOD bending vibrations of functional D(2)O molecules during the S-state cycle of the WOC by means of Fourier transform infrared (FTIR) difference spectroscopy. Flash-induced FTIR difference spectra upon S-state transitions were measured using the PSII core complexes from Thermosynechococcus elongatus moderately deuterated with D(2)(16)O and D(2)(18)O. D(2)(16)O-minus-D(2)(18)O double difference spectra at individual S-state transitions exhibited six to eight peaks arising from the D(16)OD/D(18)OD bending vibrations in the 1250-1150 cm(-1) region. This observation indicates that at least two water molecules, not in any deprotonated forms, participate in the reaction at each S-state transition throughout the cycle. Most of the peaks exhibited clear counter peaks with opposite signs at different transitions, reflecting a series of reactions of water molecules at the catalytic site. In contrast, negative bands at similar to 1240 cm(-1) in the S(2) -> S(3), S(3) -> S(0), and possibly S(0) -> S(1) transitions, for which no clear counter peaks were found in other transitions, can be interpreted as insertion of substrate water into the WOC from a water cluster in the proteins. The characteristics of the weakly D-bonded OD stretching bands were consistent with the insertion of substrate from internal water molecules in the S(2) -> S(3) and S(3) -> S(0) transitions. The results of this study show that FTIR detection of the DOD bending vibrations is a powerful method for investigating the molecular mechanism of photosynthetic water oxidation as well as other enzymatic reactions involving functional water molecules.
  • Natsuko Inoue-Kashino, Takeshi Takahashi, Akiko Ban, Miwa Sugiura, Yuichiro Takahashi, Kazuhiko Satoh, Yasuhiro Kashino
    PHOTOSYNTHESIS RESEARCH 98 (1-3) 323 - 335 0166-8595 2008/10 [Peer-reviewed]
     Scientific journal 
    Ycf12 (Psb30) is a small hydrophobic subunit of photosystem II (PS II) complexes found in the cyanobacterium, Thermosynechococcus elongatus. However, earlier intense proteomic analysis on the PS II complexes from the cyanobacterium, Synechocystis 6803, could not detect Psb30. In this work, we generated a mutant of Synechocystis 6803 in which a hexa-histidine tag was fused to the C-terminus of Synechocystis Psb30. The mutant accumulated fully functional PS II complexes. Purification of Psb30 by metal affinity chromatography from thylakoid extracts resulted in co-purification of an oxygen-evolving PS II complex with normal subunit composition. This result indicates that Psb30 is expressed and stably associated with the PS II complex in Synechocystis. The histidine-tagged Psb30 in the purified PS II complex was not detected by staining or anti-polyhistidine antibodies. We also generated a mutant in which ycf12 was disrupted. The mutant grew photosynthetically and showed no significant phenotype under moderate growth conditions. Purified PS II complexes from the disruptant showed an oxygen-evolving activity comparable to wild type under low irradiance. However, it showed a remarkably lower activity than wild type under high irradiance. Thus Psb30 is required for the efficient function of PS II complexes, particularly under high irradiance conditions.
  • Joseph L. Hughes, A. William Rutherford, Miwa Sugiura, Elmars Krausz
    PHOTOSYNTHESIS RESEARCH 98 (1-3) 199 - 206 0166-8595 2008/10 [Peer-reviewed]
     Scientific journal 
    We monitored illuminated-minus-dark absorption difference spectra in the range of 450-1100 nm induced by continuous illumination at 8 K of photosystem II (PSII) core complexes from Thermosynechococcus elongatus. The photo-induced oxidation of the side-path donors Cytb(559), beta-carotene and chlorophyll Z, as well as the concomitant stable (t(1/2) > 1 s) reduction of the first plastoquinone electron acceptor, Q(A) (monitored by the well-known 'C550' shift), were quantified as a function of the absorbed photons per PSII. The Q(A) photo-induced reduction data can be described by three distinct quantum efficiency distributions: (i) a very high efficiency of similar to 0.5-1, (ii) a middle efficiency with a very large range of similar to 0.014-0.2, and (iii) a low efficiency of similar to 0.002. Each of the observed side-path donors exhibited similar quantum efficiency distributions, which supports a branched pathway model for side-path oxidation where beta-carotene is the immediate electron donor to the photo-oxidized chlorophyll (P680(+)). The yields of the observed side-path donors account quantitatively for the wide middle efficiency range of photo-induced Q(A) reduction, but not for the PSII fractions that exhibit the highest and lowest efficiencies. The high-efficiency component may be due to Tyr(Z) oxidation.
  • Alain Boussac, Jean-Marc Verbavatz, Miwa Sugiura
    PHOTOSYNTHESIS RESEARCH 98 (1-3) 285 - 292 0166-8595 2008/10 [Peer-reviewed]
     Scientific journal 
    This report describes a protocol to incorporate isotopically labelled aromatic amino acids into the proteins of the thermophilic cyanobacterium Thermosynechoccus elongatus. By using the EPR signal of the two redox active tyrosines of Photosystem II, Tyr(D)(center dot) and Tyr(Z)(center dot), as spectroscopic probes it is shown that labelled tyrosines can be incorporated with a high yield in this cyanobacterium. The production of a fully (13)C- or (2)H-labelled enzyme is also described.
  • Naoko Ishida, Miwa Sugiura, Fabrice Rappaport, Thanh-Lan Lai, A. William Rutherford, Alain Boussac
    JOURNAL OF BIOLOGICAL CHEMISTRY 283 (19) 13330 - 13340 0021-9258 2008/05 [Peer-reviewed]
     Scientific journal 
    The active site for water oxidation in photosystem II goes through five sequential oxidation states (S(0) to S(4)) before O(2) is evolved. It consists of a Mn(4)Ca cluster close to a redox-active tyrosine residue (Tyr(Z)). Cl(-) is also required for enzyme activity. To study the role of Ca(2+) and Cl(-) in PSII, these ions were biosynthetically substituted by Sr(2+) and Br(-), respectively, in the thermophilic cyanobacterium Thermosynechococcus elongatus. Irrespective of the combination of the non-native ions used (Ca/Br, Sr/Cl, Sr/Br), the enzyme could be isolated in a state that was fully intact but kinetically limited. The electron transfer steps affected by the exchanges were identified and then investigated by using time-resolved UV-visible absorption spectroscopy, time-resolved O(2) polarography, and thermoluminescence spectroscopy. The effect of the Ca(2+)/Sr(2+) and Cl(-)/Br(-) exchanges was additive, and the magnitude of the effect varied in the following order: Ca/Cl < Ca/Br < Sr/Cl < Sr/Br. In all cases, the rate of O(2) release was similar to that of the S(3)Tyr(Z)(center dot) to S(0)Tyr(Z) transition, with the slowest kinetics (i.e. the Sr/Br enzyme) being approximate to 6-7 slower than in the native Ca/Cl enzyme. This slowdown in the kinetics was reflected in a decrease in the free energy level of the S(3) state as manifest by thermoluminescence. These observations indicate that Cl(-) is involved in the water oxidation mechanism. The possibility that Cl(-) is close to the active site is discussed in terms of recent structural models.
  • Miwa Sugiura, Alain Boussac, Takumi Noguchi, Fabrice Rappaport
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1777 (4) 331 - 342 0005-2728 2008/04 [Peer-reviewed]
     Scientific journal 
    The influence of the histidine axial ligand to the P-D1 chlorophyll of photosystem II on the redox potential and spectroscopic properties of the primary electron donor, P-680, was investigated in mutant oxygen-evolving photosystem II (PSII) complexes purified from the thermophilic cyanobacterium Thermosynechococcus elongatus. To achieve this aim, a mutagenesis system was developed in which the psbA(1) and psbA(2) genes encoding D1 were deleted from a His-tagged CP43 strain (to generate strain WT*) and mutations D1-H198A and D1-H198Q were introduced into the remaining psbA(3) gene. The O-2-evolving activity of His-tagged PSII isolated from WT* was found to be significantly higher than that measured from His-tagged PSII isolated from WT in which psbA(1) is expected to be the dominantly expressed form. PSII purified from both the D1-H198A and D1-H198Q mutants exhibited oxygen-evolving activity as high as that from WT*. Surprisingly, a variety of kinetic and spectroscopic measurements revealed that the D1-H198A and D1-H198Q mutations had little effect on the redox and spectroscopic properties of P680, in contrast to the earlier results from the analysis of the equivalent mutants constructed in Synechoeystis sp. PCC 6803 [B.A. Diner, E. Schlodder, P.J. Nixon, W.J. Coleman, F. Rappaport, J. Lavergne, W.F. Vermaas, D.A. Chisholm, Site-directed mutations at D1-His 198 and D2-His197 of photosystem II in Synechocystis PCC 6803: sites of primary charge separation and cation and triplet stabilization, Biochemistry 40 (2001) 9265-92811. We conclude that the nature of the axial ligand to PD1 is not an important determinant of the redox and spectroscopic properties Of P680 in T elongatus. (C) 2008 Elsevier B.V All rights reserved.
  • Chika Aoyama, Hiroyuki Suzuki, Miwa Sugiura, Takumi Noguchi
    BIOCHEMISTRY 47 (9) 2760 - 2765 0006-2960 2008/03 [Peer-reviewed]
     Scientific journal 
    Bicarbonate is known to be required for the maximum activity of photosystem II. Although it is well established that bicarbonate is bound to the northeme iron to regulate the quinone reactions, the effect of bicarbonate on oxygen evolution is still controversial, and its binding site and exact physiological roles remain to be clarified. In this study, the structural coupling of bicarbonate to the oxygen-evolving center (OEC) was studied using Fourier transform infrared (FTIR) difference spectroscopy. Flash-induced FTIR difference spectra during the S-state cycle of OEC were recorded using the PSII core complexes from Thermosynechococcus elongatus in the presence of either unlabeled bicarbonate or (13)C-bicarbonate. The H(12)CO(3)-minus-H(13)CO(3)-double difference spectra showed prominent bicarbonate bands at the first flash, whereas no appreciable bands were detected at the second to fourth flashes. The bicarbonate bands at the, first flash were virtually identical to those from the nonheme iron, which was preoxidized by ferricyanide and photoreduced by a single flash, recorded using Mn-depleted PSII complexes. Using the bicarbonate bands of the nonheme iron as an internal standard, it was concluded that no bicarbonate band arising from OEC exists in the S-state FTIR spectra. This conclusion indicates that bicarbonate is not affected by the structural changes in OEC upon the four S-state transitions. It is thus strongly suggested that bicarbonate is neither a ligand to the Mn cluster nor a cofactor closely coupled to OEC, although the possibility cannot be fully excluded that nonexchangeable bicarbonate exists in OEC as a constituent of the Mn-cluster core. The data also provide strong evidence that bicarbonate does not function as a substrate or a catalytic intermediate. Bicarbonate may play major roles in the photoassembly process of the Mn cluster and in the stabilization of OEC by a rather indirect interaction.
  • Alain Boussac, Miwa Sugiura, Thanh-Lan Lai, A. William Rutherford
    PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES 363 (1494) 1203 - 1210 0962-8436 2008/03 [Peer-reviewed]
     Scientific journal 
    The active site for water oxidation in photosystem II (PSII) consists of a Mn(4)Ca cluster close to a redox-active tyrosine residue (TyrZ). The enzyme cycles through five sequential oxidation states (S(0) to S(4)) in the water oxidation process. Earlier electron paramagnetic resonance (EPR) work showed that metalloradical states, probably arising from the Mn(4) cluster interacting with TyrZ(center dot), can be trapped by illumination of the S(0), S(1) and S(2) states at cryogenic temperatures. The EPR signals reported were attributed to S(0)TyrZ(center dot), S(1)TyrZ(center dot) and S(2)TyrZ(center dot), respectively. The equivalent states were examined here by EPR in PSII isolated from Thermosynechococcus elongatus with either Sr or Ca associated with the Mn(4) cluster. In order to avoid spectral contributions from the second tyrosyl radical, TyrD(center dot), PSII was used in which Tyr160 of D2 was replaced by phenylalanine. We report that the metalloradical signals attributed to TyrZ(center dot) interacting with the Mn cluster in S(0), S(1), S(2) and also probably the S(3) states are all affected by the presence of Sr. Ca/Sr exchange also affects the non-haem iron which is situated approximately 44 angstrom units away from the Ca site. This could relate to the earlier reported modulation of the potential of QA by the occupancy of the Ca site. It is also shown that in the S3 state both visible and near-infrared light are able to induce a similar Mn photochemistry.
  • James W. Murray, Karim Maghlaoui, Joanna Kargul, Naoko Ishida, Thanh-Lan Lai, A. William Rutherford, Miwa Sugiura, Alain Boussac, James Barber
    ENERGY & ENVIRONMENTAL SCIENCE 1 (1) 161 - 166 1754-5692 2008 [Peer-reviewed]
     Scientific journal 
    Bromide anomalous X-ray diffraction analyses have been used to locate chloride binding sites in the vicinity of the water splitting/oxygen evolving centre (OEC) of Photosystem II. Three-dimensional crystals of PSII from Thermosynechococcus elongatus were grown from (i) isolated PSII crystals infiltrated with bromide or (ii) PSII obtained from cells cultured in a medium in which the chloride content was totally replaced by bromide. In either case, the anomalous diffraction yielded the same result, the existence of two bromide binding sites in the vicinity of the OEC. Neither are in the first coordination sphere of the Mn and Ca ions which form the catalytic centre of the OEC, being about 6 to 7 angstrom from the metal-cluster. Site 1 is located close to the side chain nitrogen of D2-K317 and the backbone nitrogen of D1-Glu333 while Site 2 is adjacent to backbone nitrogens of CP43-Glu354 and D1-Asn338. Their positioning close to postulated hydrophilic channels may suggest a role in proton removal from, or substrate access to, the OEC.
  • Ryouta Takahashi, Miwa Sugiura, Takumi Noguchi
    BIOCHEMISTRY 46 (49) 14245 - 14249 0006-2960 2007/12 [Peer-reviewed]
     Scientific journal 
    The redox-active tyrosine Y-D (D2-Tyr160) in photosystem II (PSII) serves as a side-path electron donor to P680. When YD is oxidized, a proton is released from phenolic OH, and a neutral radical Y-D(center dot) is formed. A hydrogen bond network around YD must be deeply involved in the mechanism of the YD reaction. In this study, we have detected water molecules structurally coupled to YD by means of Fourier transform infrared (FTIR) spectroscopy. Light-induced Y-D(center dot)/Y-D FTIR difference spectrum of a hydrated film of the PSII core complexes from Thermosynechococcus elongatus showed major signals at 3636(-)/3617(+) and 3594(+)/3585(-) cm(-1) in the weakly hydrogen bonded OH stretching region. These peaks downshifted by 11-12 cm(-1) upon (H2O)-O-18 substitution and almost disappeared upon H/D exchange, and hence, they were definitely assigned to the water OH vibrations. Small intramolecular couplings of 3-6 cm(-1) estimated from the OH frequencies of residual HOD species in a deuterated film indicate that these OH signals, arise from two different water molecules that have significantly asymmetric hydrogen bond structures. Similar OH signals were observed in PSII-enriched membranes from spinach, suggesting that two water molecules commonly exist near YD irrespective of biological species. These water molecules are coupled to YD most probably through a hydrogen bond network or one of them possibly interacts directly with YD, and thus, they may play crucial roles in the YD reaction by forming a proton-transfer pathway and tuning the redox potential Of Y-D.
  • Yasuhiro Kashino, Takeshi Takahashi, Natsuko Inoue-Kashino, Akiko Ban, Yohei Ikeda, Kazuhiko Satoh, Miwa Sugiura
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1767 (11) 1269 - 1275 0005-2728 2007/11 [Peer-reviewed]
     Scientific journal 
    The latest crystallographic model of the cyanobacterial photosystem II (PS II) core complex added one transmembrane low molecular weight (LMW) component to the previous model, suggesting the presence of an unknown transmembrane LMW component in PS II. We have investigated the polypeptide composition in highly purified intact PS II core complexes from Thermosynechococcus elongatus, the species which yielded the PS II crystallographic models described above, to identify the unknown component. Using an electrophoresis system specialized for separation of LMW hydrophobic proteins, a novel protein of similar to 5 kDa was identified as a PS II component. Its N-terminal amino acid sequence was identical to that of Ycf12. The corresponding gene is known as one of the ycf (hypothetical chloroplast reading frame) genes, ycf12, and is widely conserved in chloroplast and cyanobacterial genomes. Nonetheless, the localization and function of the gene product have never been assigned. Our finding shows, for the first time, that ycf12 is actually expressed as a component of the PS II complex in the cell, revealing that a previously unidentified transmembrane protein exists in the PS II core complex. (c) 2007 Elsevier B. All rights reserved.
  • Miwa Sugiura, Mihaela N. Georgescu, Masaaki Takahashi
    PLANT AND CELL PHYSIOLOGY 48 (7) 1022 - 1035 0032-0781 2007/07 [Peer-reviewed]
     Scientific journal 
    Chloroplasts take up cytosolic nitrite during nitrate assimilation. In this study we identified a nitrite transporter located in the chloroplasts of higher plants. The transporter, CsNitr1- L, a member of the proton- dependent oligopeptide transporter ( POT) family, was detected during light- induced chloroplast development in de- etiolating cucumber seedlings. We detected a CsNitr1- L - green fluorescent protein ( GFP) fusion protein in the chloroplasts of leaf cells and found that an immunoreactive 51 kDa protein was present in the isolated inner envelope membrane of chloroplasts. CsNitr1- L has an isoform, CsNitr1- S, with an identical 484 amino acid core sequence; however, in CsNitr1- S the 120 amino acid N- terminal extension is missing. Saccharomyces cerevisiae cells expressing CsNitr1- S absorbed nitrite from an acidic medium at a slower rate than mock- transformed control cells, and accumulated nitrite to only one- sixth the concentration of the control cells, suggesting that CsNitr1- S enhances the efflux of nitrite from the cell. Insertion of T- DNA in a single CsNitr1- L homolog ( At1g68570) in Arabidopsis resulted in nitrite accumulation in leaves to more than five times the concentration found in the wild type. These results show that it is possible that both CsNitr1- L and CsNitr1- S encode efflux- type nitrite transporters, but with different subcellular localizations. CsNitr1- L may possibly load cytosolic nitrite into chloroplast stroma in the chloroplast envelope during nitrate assimilation. The presence of genes homologous to CsNitr1- L in the genomes of Arabidopsis and rice indicates that facilitated nitrite transport is of general physiological importance in plant nutrition.
  • Tatsunori Okubo, Tatsuya Tomo, Miwa Sugiura, Takumi Noguchi
    BIOCHEMISTRY 46 (14) 4390 - 4397 0006-2960 2007/04 [Peer-reviewed]
     Scientific journal 
    The structure and the electronic properties of P680 and its radical cation in photosystem II (PSII) were studied by means of Fourier transform infrared spectroscopy (FTIR). Light-induced P680(+)/P680 FTIR difference spectra in the mid- and near-IR regions were measured using PSII membranes from spinach, core complexes from Thermosynechococcus elongatus, and reaction center (RC) complexes (D1-D2-Cytb559) from spinach. The spectral features of the former two preparations were very similar, indicating that the structures of P680 and its radical cation are virtually identical between membranes and cores and between plants and cyanobacteria. In sharp contrast, the spectrum of the RC complexes exhibited significantly different features. A positive doublet at similar to 1724 and similar to 1710 cm(-1) due to the 13(1)-keto CO stretches of P680(+) in the membrane and core preparations were changed to a prominent single peak at 1712 cm(-1) in the RC complexes. This observation was interpreted to indicate that a positive charge on P680(+) was extensively delocalized over the chlorophyll dimer in RC, whereas it was mostly localized on one chlorophyll molecule (70-80%) in intact P680. The significant change in the electronic structure of P680(+) in RC was supported by a dramatic change in the characteristics of a broad intervalence band in the near-IR region and relatively large shifts of chlorin ring bands. It is proposed that the extensive charge delocalization in P680(+) mainly causes the decrease in the redox potential of P680(+)/P680 in isolated RC complexes. This potential decrease explains the well-known phenomenon that Y(Z) is not oxidized by P680(+) in RC complexes.
  • Sun Un, Alain Boussac, Miwa Sugiura
    BIOCHEMISTRY 46 (11) 3138 - 3150 0006-2960 2007/03 Scientific journal 
    The Mn4Ca cluster of photosystem II (PSII) goes through five sequential oxidation states (S-0-S-4) in the water oxidation process that also involves a tyrosine radical intermediate (Tyr(Z)(center dot)). An S(2)Tyr(Z)(center dot) state in which the Mn4Ca cluster and Tyr(Z)(center dot) are magnetically coupled to each other and which is characterized by a distinct "split-signal" EPR spectrum can be generated in acetate-treated PSII. This state was examined by high-field EPR (HFEPR) in PSII from Thermosynechococcus elongatus isolated from a D2-Tyr160Phe mutant to avoid spectral contributions from Tyr(D)(center dot). In contrast to the same state in plants, both antiferromagnetic and ferromagnetic spin-spin couplings were observed. The intrinsic g values of Tyr(Z)(center dot) in the coupled state were directly measured from the microwave frequency dependence of the HFEPR spectrum. The Tyr(Z)(center dot) g(x) value in the antiferromagnetic centers was 2.0083, indicating that the coupled radical was in a less electropositive environment than in Mn-depleted PSII. Two g(x) values were found in the ferromagnetically coupled centers, 2.0069 and 2.0079. To put these values in perspective, the second redox-active tyrosine, Tyr(D)(center dot), was examined in various electrostatic environments. The Tyr(D)(center dot) g(x) value changed from 2.0076 in the wild type to 2.0095 when the hydrogen bond from histidine 189 to Tyr(D)(center dot) was removed using the D2-His189Leu mutant, indicating a change to a significantly less electropositive environment. BLY3P/6-31+G** density functional calculations on the hydrogen-bonded p-ethylphenoxy radical-imidazole supermolecular model complex showed that the entire range of Tyr(center dot) g(x) values, from 2.0065 to 2.0095, could be explained by the combined effects of hydrogen bonding and the dielectric constant of the local protein environment.
  • Hiroyuki Suzuki, Yuta Taguchi, Miwa Sugiura, Alain Boussac, Takumi Noguchi
    BIOCHEMISTRY 45 (45) 13454 - 13464 0006-2960 2006/11 Scientific journal 
    A Ca2+ ion is an indispensable element in the oxygen-evolving Mn cluster in photosystem II (PSII). To investigate the structural relevance of Ca2+ to the Mn cluster, the effects of Sr2+ substitution for Ca2+ on the structures and reactions of ligands to the Mn cluster during the S-state cycle were investigated using flash-induced Fourier transform infrared ( FTIR) difference spectroscopy. FTIR difference spectra representing the four S-state transitions, S-1 -> S-2, S-2 -> S-3, S-3 -> S-0, and S-0 -> S-1, were recorded by applying four consecutive flashes either to PSII core complexes from Thermosynechococcus elongatus or to PSII-enriched membranes from spinach. The spectra were also recorded using biosynthetically Sr(2+)substituted PSII core complexes from T. elongatus and biochemically Sr2+-substituted PSII membranes from spinach. Several common spectral changes upon Sr2+ substitution were observed in the COO(-)stretching region of the flash-induced spectra for both preparations, which were best expressed in Ca2+-minus-Sr2+ double difference spectra. The significant intensity changes in the symmetric COO- peaks at similar to 1364 and similar to 1418 cm(-1) at the first flash were reversed as opposite intensity changes at the third flash, and the slight shift of the similar to 1446 cm-1 peak at the second flash corresponded to the similar but opposite shift at the fourth flash. Analyses of these changes suggest that there are at least three carboxylate ligands whose structures are significantly perturbed by Ca2+/Sr2+ exchange. They are (1) the carboxylate ligand having a bridging or unidentate structure in the S2 and S3 states and perturbed in the S-1 -> S-2 and S-3 -> S-0 transitions, (2) that with a chelating or bridging structure in the S1 and S0 states and perturbed also in the S-1 -> S-2 and S-3 -> S-0 transitions, and (3) that with a chelating structure in the S-3 and S-0 states and changes in the S-2 -> S-3 and S-0 -> S-1 transitions. Taking into account the recent FTIR studies using site-directed mutagenesis and/or isotope substitution [Chu et al. (2004) Biochemistry 43,3152- 3116; Kimura et al. (2005) J. Biol. Chem. 280, 2078-2083; Strickler et al. (2006) Biochemistry 45, 8801-8811], it was concluded that these carboxylate groups do not originate from either D1-Ala344 (C-terminus) or D1-Glu189, which are located near the Ca2+ ion in the X-ray crystallographic model of the Mn cluster. It was thus proposed that if the X-ray model is correct, the above carboxylate groups sensitive to Sr2+ substitution are ligands to the Mn ions strongly coupled to the Ca2+ ion rather than direct ligands to Ca2+.
  • Sustiprijatno, Miwa Sugiura, Ken'ichi Ogawa, Masaaki Takahashi
    Plant Biotechnology 23 (1) 47 - 54 1347-6114 2006 International conference proceedings 
    Loading of cytosolic nitrite into the chloroplast in nitrate assimilation of rice was modified by introducing gene for chloroplastic nitrite transport from cucumber. Rice (Oryza sativa L. japonica cv. Nipponbare) was transformed with a cDNA (CsNitr1-L) that encodes a nitrite transporter of cucumber under the control of the CaMV35S promoter. CsNitr1-L transgenic rice grown by hydroponics with nitrate supplied as the sole nitrogen source grew as well as plants grown with ammonia. In contrast the growth of the untransformed or mock-transformed control rice was retarded on nitrate-containing medium by about 60% compared to plants grown with ammonia. Nitrite was not beneficial to the growth of the untransformed or mock-transformed control rice but sustained that of CsNitr1-L transgenic rice. Low steady-state concentration of nitrite in leaves as well as delayed non-photochemical quenching of chlorophyll fluorescence in CsNitr1-L transgenic rice seems indicative of higher nitrite use in chloroplasts.
  • A Boussac, M Sugiura, D Kirilovsky, AW Rutherford
    PLANT AND CELL PHYSIOLOGY 46 (6) 837 - 842 0032-0781 2005/06 Scientific journal 
    The Mn4Ca complex that is involved in water oxidation in PSII is affected by near-infrared (NIR) light in certain redox states and these phenomena can be monitored by electron paramagnetic resonance (EPR) at low temperature. Here we report the action spectra of the NIR effects in the S-2 and S-3 states in PSII from plants and the thermophilic cyanobacterium Thermosynechococcus elongatus. The action spectra obtained are very similar in both S states, indicating the presence of the same photoactive form of the Mn4Ca complex in both states. Since the chemical nature of the photoactive species is not known, an unequivocal interpretation of this result cannot be made; however, it appears to be more easily reconciled with the view that the redox state of the Mn4Ca cluster does not change from the S-2 to the S-3 transition, at least in those centers sensitive to NIR light. The temperature dependence of the NIR effect and the action spectra for S-2 indicate the presence of structural heterogeneity in the Mn4Ca cluster.
  • J Maly, J Krejci, M Ilie, L Jakubka, J Masojidek, R Pilloton, K Sameh, P Steffan, Z Stryhal, M Sugiura
    ANALYTICAL AND BIOANALYTICAL CHEMISTRY 381 (8) 1558 - 1567 1618-2642 2005/04 Scientific journal 
    Mass transport of the bulk of the analyte to the electrode and through the bioactive layer can be significantly improved by use of the nanoelectrode array and defined arrangement of protein film. This phenomenon has been studied by (i) atomic-force microscopy, (ii) electrochemical measurements of PSII activity, and (iii) digital simulations for an oriented monolayer of histidine-tagged photosystem II (PSII) immobilized on nitrilotriacetic acid (NTA)-modified gold electrodes. The output signal of the electrochemical biosensor is controlled by (i) mass transport from the bioactive layer to electrode and (ii) mass transport between the bulk of the analyte and the electrode. Mass transport through the bioactive layer was electrochemically studied for PSII self-assembled on gold screen-printed electrodes. A densely packed monolayer of PSII has a significant shielding effect toward the diffusion of redox mediator duroquinone (DQ). Mass transport to the planar electrode surface was improved by co-immobilization of bovine-serum albumin (BSA) as spacer biomolecule in the monolayer of PSII. Correlation between the electrochemical properties and surface arrangement of the resulting protein films was clearly observable and confirmed the improved mass-transport properties of structured enzyme monolayers. On the basis of this observation, the application of a bottom-up approach for improvement of electrode performance was proposed and digitally simulated for an infinite array of electrodes ranging in diameter from 50 nm to 5 mu m. The nanoelectrode array, with the optimum time window selected for measurements, enables enhancement of mass transport between the bulk of the analyte and the macroelectrode by a factor of up to 50 in comparison with "classical" planar electrodes. Use of a time window enables minimization of crosstalk between individual electrodes in the array. The measurements require methods which suppress the double-layer capacity.
  • H Suzuki, M Sugiura, T Noguchi
    BIOCHEMISTRY 44 (5) 1708 - 1718 0006-2960 2005/02 [Peer-reviewed]
     Scientific journal 
    pH dependence of the efficiencies of the flash-induced S-state transitions in the oxygen-evolving center (OEC) was studied by means of Fourier transform infrared (FTIR) difference spectroscopy using photosystem II (PSII) core complexes from the thermophilic cyanabactrium Thermosynechoccocus elongatus. The PSII core complexes dark-adapted at different pHs in the presence of ferricyanide as an electron acceptor were excited by four consecutive saturating laser flashes, and FTIR difference spectra induced by each flash were recorded in the region of 1800-1200 cm(-1). Each difference spectrum was fitted with a linear combination of standard spectra measured at pH 6.0, which represent the spectra upon individual S-state transitions, and the transition efficiencies were estimated from the fitting parameters. It was found that the S(1) --> S(2) transition probability is independent of pH throughout the pH region of 3.5-9.5, while the S(2) --> S(3), S(3) --> S(0), and S(0) --> S(1) transition probabilities decrease at acidic pH with pK values of 3.6 +/- 0.2, 4.2 +/- 0.3, and 4.7 +/- 0.5, respectively. These findings, i.e., the pH-independent S(1) - S2 transition probability and the pK values for the inhibition in the acidic range of the other three transitions, were in good agreement with recent results obtained by electron paramagnetic resonance measurements for PSII-enriched membranes of spinach [Bernat, G., Morvaridi, F., Feyziyev, Y., and Styring, S. (2002) Biochemistry 41, 5830-5843]. On the basis of this correspondence for quite different types of PSII preparations exhibiting marked difference in the pH dependence of the apparent proton release pattern, it is concluded that the inhibition of the S(2) --> S(3), S(3) --> S(0), and S(0) --> S(1) transitions in the acidic region is an inherent property of the OEC. This feature probably reflects proton release from substrate water in these three transitions. On the other hand, all of the S-state transitions remained generally efficient up to pH 9.5 in the alkaline region, except for a slight decrease of the S(3) --> S(0) transition probability above pH 8 (pK - 10). This observation partly differs from the tendency reported for spinach preparations, suggesting that a mechanism different from that in the acidic region is responsible for the transition efficiencies in the alkaline region.
  • D Kirilovsky, M Roncel, A Boussac, A Wilson, JL Zurita, JM Ducruet, H Bottin, M Sugiura, JM Ortega, AW Rutherford
    JOURNAL OF BIOLOGICAL CHEMISTRY 279 (51) 52869 - 52880 0021-9258 2004/12 [Peer-reviewed]
     Scientific journal 
    Cytochrome c(550) is one of the extrinsic Photosystem II subunits in cyanobacteria and red algae. To study the possible role of the heme of the cytochrome c(550) we constructed two mutants of Thermosynechococcus elongatus in which the residue His-92, the sixth ligand of the heme, was replaced by a Met or a Cys in order to modify the redox properties of the heme. The H92M and H92C mutations changed the midpoint redox potential of the heme in the isolated cytochrome by +125 mV and -30 mV, respectively, compared with the wild type. The binding-induced increase of the redox potential observed in the wild type and the H92C mutant was absent in the H92M mutant. Both modified cytochromes were more easily detachable from the Photosystem II compared with the wild type. The Photosystem II activity in cells was not modified by the mutations suggesting that the redox potential of the cytochrome c(550) is not important for Photosystem II activity under normal growth conditions. A mutant lacking the cytochrome c(550) was also constructed. It showed a lowered affinity for Cl- and Ca2+ as reported earlier for the cytochrome c(550)-less Synechocystis 6803 mutant, but it showed a shorter lived S(2)Q(B)(-) state, rather than a stabilized S-2 state and rapid deactivation of the enzyme in the dark, which were characteristic of the Synechocystis mutant. It is suggested that the latter effects may be caused by loss ( or weaker binding) of the other extrinsic proteins rather than a direct effect of the absence of the cytochrome c(550).
  • M Sugiura, F Rappaport, K Brettel, T Noguchi, AW Rutherford, A Boussac
    BIOCHEMISTRY 43 (42) 13549 - 13563 0006-2960 2004/10 [Peer-reviewed]
     Scientific journal 
    Site-directed mutagenesis in the photosystem II (PSII) oxygen-evolving enzyme was achieved in the thermophilic cyanobacterium Thermosynechococcus elongatus. PSII from this species is the focus of attention because its robustness makes it suitable for enzymological and biophysical studies. PSII, which lacks the redox-active tyrosine Tyro, was engineered by substituting a phenylalanine for tyrosine 160 of the D2 protein. An aim of this work was to engineer a mutant for spectroscopy, in particular, for EPR, on the active enzyme. The Tyr(D)(.) EPR signal was monitored in whole cells (i) to control the expression level of the two genes (psbD(1) and psbD(2)) encoding D2 and (ii) to assess the success of the mutagenesis. Both psbD(1) and psbD(2) could be expressed, and recombination occurred between them. The D2-Y160F mutation was introduced into psbD(1) after psbD(2) was deleted and a His-tag was attached to the CP43 protein. The effects of the Y160F mutation were characterized in cells, thylakoids, and isolated PSII. The efficiency of enzyme function under the conditions tested was unaffected. The distribution and lifetime of the redox states (S-n states) of the enzyme cycle were modified, with more So in the dark and no rapid decay phase of S-3. Although not previously reported, these effects were expected because Tyr(D)(.) is able to oxidize S-0 and Tyr(D) is able to reduce S-2 and S-3. Slight changes in the difference spectra in the visible and infrared recorded upon the formation and reduction of the chlorophyll cation P-680(+) and kinetic measurements of P-680(+) reduction indicated minor structural perturbations, perhaps in the hydrogen-bonding network linking Tyr(D) and P-680, rather than electrostatic changes associated with the loss of a charge from Tyr(D)(.)(H+). We show here that this fully active preparation can provide spectra from the Mn4CaO4 complex and associated radical species uncontaminated by Tyr(D)(.).
  • J Maly, C Di Meo, M De Francesco, A Masci, J Masojidek, M Sugiura, A Volpe, R Pilloton
    BIOELECTROCHEMISTRY 63 (1-2) 271 - 275 1567-5394 2004/06 [Peer-reviewed]
     Scientific journal 
    Electrochemical synthesis of nickel-nitrilotriacetic acid (Ni-NTA) chelators, for subsequent immobilization of (HiS)(6)-tagged proteins (Photosystem II (PSII) as model molecule), on Au or Au-graphite electrodes is compared to chemical synthesis. Results show: (i) higher Ni-NTA surface density, (ii) shorter treatment time (1-12 min vs. 16 h normally needed for self-assembled monolayer (SAM)), (iii) possibility of addressing the chelator to only one Au electrode, in a sensor mu-array. (C) 2004 Elsevier B.V. All rights reserved.
  • A Boussac, F Rappaport, P Carrier, JM Verbavatz, R Gobin, D Kirilovsky, AW Rutherford, M Sugiura
    JOURNAL OF BIOLOGICAL CHEMISTRY 279 (22) 22809 - 22819 0021-9258 2004/05 [Peer-reviewed]
     Scientific journal 
    The thermophilic cyanobacterium, Thermosynechococcus elongatus, has been grown in the presence of Sr2+ instead of Ca2+ with the aim of biosynthetically replacing the Ca2+ of the oxygen-evolving enzyme with Sr2+. Not only were the cells able to grow normally with Sr2+, they actively accumulated the ion to levels higher than those of Ca2+ in the normal cultures. A protocol was developed to purify a fully active Sr2+-containing photosystem II (PSII). The modified enzyme contained a normal polypeptide profile and 1 strontium/4 manganese, indicating that the normal enzyme contains 1 calcium/4 manganese. The Sr2+- and Ca2+-containing enzymes were compared using EPR spectroscopy, UV-visible absorption spectroscopy, and O-2 polarography. The Ca2+/Sr2+ exchange resulted in the modification of the EPR spectrum of the manganese cluster and a slower turnover of the redox cycle (the so-called S-state cycle), resulting in diminished O-2 evolution activity under continuous saturating light: all features reported previously by biochemical Ca2+/Sr2+ exchange in plant PSII. This allays doubts that these changes could be because of secondary effects induced by the biochemical treatments themselves. In addition, the Sr2+-containing PSII has other kinetics modifications: 1) it has an increased stability of the S-3 redox state; 2) it shows an increase in the rate of electron donation from Tyr(D), the redox-active tyrosine of the D-2 protein, to the oxygen-evolving complex in the S-3-state forming S-2; 3) the rate of oxidation of the S-0-state to the S-1-state by Tyr(D)(.) is increased; and 4) the release of O-2 is slowed down to an extent similar to that seen for the slow-down of the S(3)Tyr(Z)(.) to S(0)Tyr(Z) transition, consistent with the latter constituting the limiting step of the water oxidation mechanism in Sr2+-substituted enzyme as well as in the normal enzyme. The replacement of Ca2+ by Sr2+ appears to have multiple effects on kinetics properties of the enzyme that may be explained by S-state-dependent shifts in the redox properties of both the manganese complex and Tyr(Z) as well as structural effects.
  • J Maly, A Masci, J Masojidek, M Sugiura, R Pilloton
    ANALYTICAL LETTERS 37 (8) 1645 - 1656 0003-2719 2004 [Peer-reviewed]
     Scientific journal 
    Two methods for monolayer immobilization of photosystem II (PSII) isolated from thermophilic cyanobacteria Synechococcus elongatus and prospects for its use as a biosensor for detection of herbicides are reported: (i) immobilization based on recombinant (HiS)(6)-tagged PSII coupled with nickel-nitrilotriacetic acid (Ni-NTA) chelator monolayer on An electrode. (ii) immobilization based on the natural PSII coupled with the protein A-anti-DI antibody modified Au electrode. Here, Cysteamine (CYS)-self-assembled monolayer (SAM)-(NTA)-PSII monolayers were compared with traditional bovine serum albumin (BSA)-glutaraldehyde (GA)-PSII crosslinked get matrix and better performances of the derived electro-chemical biosensors were pointed out. Better diffusion of inhibitors and mediators resulted in improved sensitivity, velocity of the response, and lower 150 for herbicides.
  • CA Kerfeld, S Yoshida, KT Tran, TO Yeates, D Cascio, H Bottin, C Berthomieu, M Sugiura, A Boussac
    JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY 8 (7) 707 - 714 0949-8257 2003/09 [Peer-reviewed]
     Scientific journal 
    The iron-containing superoxide dismutase (FeSOD) from the thermophilic cyanobacterium Thermosynechococcus elongatus has been isolated. The protein crystallizes readily and we have determined the structure to 1.6 Angstrom resolution. This is the first structural characterization of an FeSOD isolated from a cyanobacterium and one of the highest resolution FeSOD structures determined to date. The activity of the T. elongatus FeSOD has been measured both at 25 degreesC and 50 degreesC and it has been spectroscopically characterized. The T. elongatus FeSOD EPR spectra at pH 5.1, 7.5 and 10.0 are similar. This indicates that no change in the geometry of the Fe-III site occurs over a wide range of pH. This is in contrast to the other FeSODs described in the literature.
  • CA Kerfeld, S Yoshida, KT Tran, TO Yeates, D Cascio, H Bottin, C Berthomieu, M Sugiura, A Boussac
    JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY 8 (7) 707 - 714 0949-8257 2003/09 [Peer-reviewed]
     Scientific journal 
    The iron-containing superoxide dismutase (FeSOD) from the thermophilic cyanobacterium Thermosynechococcus elongatus has been isolated. The protein crystallizes readily and we have determined the structure to 1.6 Angstrom resolution. This is the first structural characterization of an FeSOD isolated from a cyanobacterium and one of the highest resolution FeSOD structures determined to date. The activity of the T. elongatus FeSOD has been measured both at 25 degreesC and 50 degreesC and it has been spectroscopically characterized. The T. elongatus FeSOD EPR spectra at pH 5.1, 7.5 and 10.0 are similar. This indicates that no change in the geometry of the Fe-III site occurs over a wide range of pH. This is in contrast to the other FeSODs described in the literature.
  • CA Kerfeld, MR Sawaya, H Bottin, KT Tran, M Sugiura, D Cascio, A Desbois, TO Yeates, D Kirilovsky, A Boussac
    PLANT AND CELL PHYSIOLOGY 44 (7) 697 - 706 0032-0781 2003/07 [Peer-reviewed]
     Scientific journal 
    First, the crystal structure of cytochrome c-550 (the psbV1 gene product) from the thermophilic cyanobacterium Thermosynechococcus elongatus has been determined to a resolution of 1.8 Angstrom. A comparison of the T elongatus cytochrome c-550 structure to its counterparts from mesophilic organisms, Synechocystis 6803 and Arthrospira maxima, suggests that increased numbers of hydrogen bonds may play a role in the structural basis of thermostability. The cytochrome c-550 in T elongatus also differs from that in Synechocystis 6803 and Arthrospira maxima in its lack of dimerization and the presence of a trigonal planar molecule, possibly bicarbonate, tightly bound to the heme propionate oxygen atoms. Cytochromes c-550 from T elongatus, Synechocystis 6803 and Arthrospira maxima exhibit different EPR spectra. A correlation has been done between the heme-axial ligands geometries and the rhombicity calculated from the EPR spectra. This correlation indicates that binding of cytochrome c-550 to Photosystem 11 is accompanied by structural changes in the heme vicinity. Second, the psbV2 gene product has been found and purified. The UV-visible, EPR and Raman spectra are reported. From the spectroscopic data and from a theoretical structural model based on the cytochrome c-550 structure it is proposed that the 6th ligand of the heme-iron is the Tyr86.
  • T Noguchi, M Sugiura
    BIOCHEMISTRY 42 (20) 6035 - 6042 0006-2960 2003/05 [Peer-reviewed]
     Scientific journal 
    Protein bands in flash-induced Fourier transform infrared (FTIR) difference spectra of the S-state cycle of photosynthetic water oxidation were analyzed by uniform N-15 and C-13 isotopic labeling of photosystem II (PS II). The difference spectra upon first- to fourth-flash illumination were obtained with hydrated (for the 1800-1200 cm(-1) region) or deuterated (for the 3500-3100 cm(-1) region) films of unlabeled, N-15-labeled, and C-13-labeled PS II core complexes from Thermosynechococcus elongatus. Shifts of band frequencies upon N-15 and C-13 labeling provided the assignments of major peaks in the regions of 3450-3250 and 1700-1630 cm(-1) to the NH stretches and amide I modes of polypeptide backbones, respectively, and the assignments of some of the peaks in the 1600-1500 cm(-1) region to the amide II modes of backbones. Other prominent peaks in the latter region and most of the peaks in the 1450-1300 cm(-1) region exhibited large downshifts upon C-13 labeling but were unchanged by N-15 labeling, and hence assigned to the asymmetric and symmetric COO- stretching vibrations, respectively, of carboxylate groups in Glu, Asp, or the C-terminus. Peak positions corresponded well with each other among the first- to fourth-flash spectra, and most of the bands in the first- and/or second-flash spectra appeared with opposite signs of intensity in the third- and/or fourth-flash spectra. This observation indicates that the protein movements in the S-1-->S-2 and/or S-2-->S-3 transitions are mostly reversed in the S-3-->S-0 and/or S-0-S-1 transitions, representing a catalytic role of the protein moieties of the water-oxidizing complex. Drastic structural changes in carboxylate groups over the S-state cycle suggest that the Asp and/or Glu side chains play important roles in the reaction mechanism of photosynthetic water oxidation.
  • M Roncel, A Boussac, JL Zurita, H Bottin, M Sugiura, D Kirilovsky, JM Ortega
    JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY 8 (1-2) 206 - 216 0949-8257 2003/01 [Peer-reviewed]
     Scientific journal 
    Redox properties of cytochrome b559 (Cyt b559) and cytochrome c550 (Cyt c550) have been studied by using highly stable photosystem II (PSII) core complex preparations from a mutant strain of the thermophilic cyanobacterium Thermosynechococcus elongatus with a histidine tag on the CP43 protein of PSII Two different redox potential forms for Cyt b559 are found in these preparations, with a midpoint redox potential (E'(m)) of + 390 mV in about half of the centers and + 275 mV in the other half. The high-potential form, whose E'(m) is pH independent, can be converted into the lower potential form by Tris washing, mild heating or alkaline pH incubation. The Em of the lowpotential form is significantly higher than that found in other photosynthetic organisms and is not affected by pH. The possibility that the heme of Cyt b559 in T. elongatus is in a more hydrophobic environment is discussed. Cyt c550 has a higher E'(m) when bound to the PSII core (-80 mV at pH 6.0) than after its extraction from the complex (-240 mV at pH 6.0). The E'(m) of Cyt c550 bound to PSII is pH independent, while in the purified state an increase of about 58 mV/pH unit is observed when the pH decreases below pH 9.0. Thus, Cyt c550 seems to have a single protonateable group which influences the redox properties of the heme. From these electrochemical measurements and from EPR controls it is proposed that important changes in the solvent accessibility to the heme and in the acid-base properties of that protonateable group could occur upon the release of Cyt c550 from PSII.
  • M Roncel, A Boussac, JL Zurita, H Bottin, M Sugiura, D Kirilovsky, JM Ortega
    JOURNAL OF BIOLOGICAL INORGANIC CHEMISTRY 8 (1-2) 206 - 216 0949-8257 2003/01 [Peer-reviewed]
     Scientific journal 
    Redox properties of cytochrome b559 (Cyt b559) and cytochrome c550 (Cyt c550) have been studied by using highly stable photosystem II (PSII) core complex preparations from a mutant strain of the thermophilic cyanobacterium Thermosynechococcus elongatus with a histidine tag on the CP43 protein of PSII Two different redox potential forms for Cyt b559 are found in these preparations, with a midpoint redox potential (E'(m)) of + 390 mV in about half of the centers and + 275 mV in the other half. The high-potential form, whose E'(m) is pH independent, can be converted into the lower potential form by Tris washing, mild heating or alkaline pH incubation. The Em of the lowpotential form is significantly higher than that found in other photosynthetic organisms and is not affected by pH. The possibility that the heme of Cyt b559 in T. elongatus is in a more hydrophobic environment is discussed. Cyt c550 has a higher E'(m) when bound to the PSII core (-80 mV at pH 6.0) than after its extraction from the complex (-240 mV at pH 6.0). The E'(m) of Cyt c550 bound to PSII is pH independent, while in the purified state an increase of about 58 mV/pH unit is observed when the pH decreases below pH 9.0. Thus, Cyt c550 seems to have a single protonateable group which influences the redox properties of the heme. From these electrochemical measurements and from EPR controls it is proposed that important changes in the solvent accessibility to the heme and in the acid-base properties of that protonateable group could occur upon the release of Cyt c550 from PSII.
  • T Noguchi, M Sugiura
    BIOCHEMISTRY 41 (52) 15706 - 15712 0006-2960 2002/12 [Peer-reviewed]
     Scientific journal 
    Photosynthetic water oxidation is performed via the light-driven S-state cycle in the water-oxidizing complex (WOC) of photosystem II (PS II). To understand its molecular mechanism, monitoring the reaction of substrate water in each S-state transition is essential. We have for the first time detected the reactions of water molecules in WOC throughout the S-state cycle by observing the OH vibrations of water using flash-induced Fourier transform infrared (FTIR) difference spectroscopy. Moderately hydrated (or deuterated) PS II core films from Synechococcus elongatus were used to obtain the FTIR difference spectra upon the first, second, third, and fourth flash illumination, representing the structural changes in the S-1 --> S-2, S-2 --> S-3, S-3 --> S-0, and S-0 --> S-1 transitions, respectively. In the weakly H-bonded OH region, bands appeared at 3617/3588 cm(-1) as a differential signal in the first-flash spectrum and at 3634, 3621, and 3612 cm(-1) with negative intensities in the second-, third-, and fourth-flash spectra, respectively. These bands shifted down by similar to940 cm(-1) upon deuteration and by similar to10 cm(-1) upon (HO)-O-18 substitution, indicating that they arise from the OH stretches of water including the substrate and its intermediates. Stronuly D-bonded OD bands of water were also identified as broad features in the range of 2600-2200 cm(-1) by taking the double difference between the spectra of (D2O)-O-16- and (D2O)-O-18-deuterated films. In addition, broad continuum features that probably arise from the large proton polarizability of H-bonds were observed around 3000, 2700, 2550, and 2600 cm(-1) in the first-, second-, third-, and fourth-flash spectra, respectively, of the hydrated PS II film, revealing changes in the H-bond network of the protein. The negative OH intensities upon the second to fourth flashes might be related to proton release from substrate water. The results presented here showed that FTIR detection of water OH(D) bands can be a powerful method for investigating the mechanism of photosynthetic water oxidation.
  • J Maly, E Illiano, M Sabato, M De Francesco, Pinto, V, A Masci, D Masci, J Masojidek, M Sugiura, R Franconi, R Pilloton
    MATERIALS SCIENCE & ENGINEERING C-BIOMIMETIC AND SUPRAMOLECULAR SYSTEMS 22 (2) 257 - 261 0928-4931 2002/12 [Peer-reviewed]
     Scientific journal 
    Monolayers of genetically modified proteins with an hexahistidine tag, (HiS)(6), were obtained by using a Ni-NTA chelator synthesized on gold-sputtered surfaces (via sulphide bonds), or on gold and graphite (via sililating agents) working electrodes of screen-printed devices. Two kinds of proteins were produced and purified for this study: (a) a recombinant antibody, derived from the 'single-chain Fv' (scFv) format, and (b) a photosystem 11 (PSII) core complex isolated from the mutant strain CP43-H of the thermophilic cyanobacterium Synechococcus elongatus. An scFv previously isolated from a synthetic 'phage display' library was further engineered with an alkaline phosphatase activity genetically added between the carboxy-terminal of the scFvs and the (HiS)6 to allow direct measurement of immobilisation. Renewable specific binding of (HiS)6 proteins to gold and graphite surfaces and fast and sensitive electrochemical or optical detection of analytes were obtained. Additionally, "on chip" protein preconcentration was conveniently achieved for biosensing purposes, starting from crude unpurified extracts and avoiding protein purification steps. (C) 2002 Elsevier Science B.V. All rights reserved.
  • T Noguchi, M Sugiura
    BIOCHEMISTRY 41 (7) 2322 - 2330 0006-2960 2002/02 [Peer-reviewed]
     Scientific journal 
    Differently hydrated films of photosystem II (PSII) core complexes from Synechococcus elongatus were prepared in a humidity-controlled infrared cell. The relative humidity was changed by a simple method of placing a different ratio of glycerol/water solution in the sealed cell. The extent of hydration of the PSII film was lowered as the glycerol ratio increased. FTIR difference spectra of the water oxidizing complex upon the first to sixth flashes were measured at 10 degreesC using these hydrated PSII films. The FTIR spectra (1800-1200 cm(-1)) of the PSII films hydrated using 20% and 40% glycerol/water showed basically the same features as those of the core sample in solution [Noguchi, T., and Sugiura, A (2001) Biochemistry 40, 1497-1502], and the prominent peaks exhibited clear period four oscillation patterns. These observations indicate that the S-state cycle properly functions in these hydrated samples. In the PSII films less hydrated, however, the efficiencies of S-state transitions decreased as the extent of hydration was lowered. This tendency was more significant in the S-2 --> S-3 and S-3 --> S-0 transitions than in the S-1 --> S-2 and S-0 --> S-1 transitions, indicating that the reactions or movements of water molecules are more strongly coupled with the former two transitions than the latter two. The implication of this observation was discussed in light of the water oxidizing mechanism especially in respect to the steps of substrate incorporation and proton release. Furthermore, in the OH stretching region (3800-3000 cm(-1)) of the first-flash spectrum, a differential signal was observed at 3618/3585 cm(-1), which was previously found in the S-2/S-1 spectrum of a frozen sample at 250 K and assigned to the water vibrations [Noguchi, T., and Sugiura, M. (2000) Biochemistry 39, 10943-10949]. The fact that the signal appeared even in rather dehydrated PSII films at a physiological temperature (10 degreesC) supported the idea that this water is located in the close vicinity of the Mn cluster and directly involved in the water oxidizing reaction. The results also showed that moderate hydration of the PSII sample made the whole OH region measurable, escaping from absorption saturation by bulk water, and thus will be a useful technique to monitor the water reactions during the S-state cycle using FTIR spectroscopy.
  • P Faller, RJ Debus, K Brettel, M Sugiura, AW Rutherford, A Boussac
    PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 98 (25) 14368 - 14373 0027-8424 2001/12 [Peer-reviewed]
     Scientific journal 
    Two symmetrically positioned redox active tyrosine residues are present in the photosystem II (PSII) reaction center. One of them, TyrZ, is oxidized in the ns-mus time scale by P680(+) and reduced rapidly (As to ms) by electrons from the Mn complex. The other one, TyrD, is stable in its oxidized form and seems to play no direct role in enzyme function. Here, we have studied electron donation from these tyrosines to the chlorophyll cation (P680+) in Mn-depleted PSII from plants and cyanobacteria. In particular, a mutant lacking TyrZ was used to investigate electron donation from TyrD. By using EPR and time-resolved absorption spectroscopy, we show that reduced TyrD is capable of donating an electron to P680+ with t1/2 approximate to 190 ns at pH 8.5 in approximately half of the centers. This rate is approximate to 10(5) times faster than was previously thought and similar to the TyrZ donation rate in Mn-depleted wild-type PSII (pH 8.5). Some earlier arguments put forward to rationalize the supposedly slow electron donation from TyrD (compared with that from TyrZ) can be reassessed. At pH 6.5, TyrZ (t(1/2) = 2-10 mus) donates much faster to P680(+) than does TyrD (t(1/2) > 150 mus). These different rates may reflect the different fates of the proton released from the respective tyrosines upon oxidation. The rapid rate of electron donation from TyrD requires at least partial localization of P680+ on the chlorophyll (P-D2) that is located on the D2 side of the reaction center.
  • T. Noguchi, M. Sugiura
    Biochemistry 40 (6) 1497 - 1502 0006-2960 2001/02 [Peer-reviewed]
     Scientific journal 
    Fourier transform infrared (FTIR) difference spectra of all flash-induced S-state transitions of the oxygen-evolving complex were measured using photosystem II (PSII) core complexes of Synechococcus elongatus. The PSII core sample was given eight successive flashes with 1 s intervals at 10 °C, and FTIR difference spectra upon individual flashes were measured. The obtained difference spectra upon the first to fourth flashes showed considerably different spectral features from each other, whereas the fifth, sixth, seventh, and eighth flash spectra were similar to the first, second, third, and fourth flash spectra, respectively. The intensities at the wave numbers of prominent peaks of the first and second flash spectra showed clear period four oscillation patterns. These oscillation patterns were well fitted with the Kok model with 13% misses. These results indicate that the first, second, third, and fourth flash spectra represent the difference spectra upon the S1 → S2, S2 → S3, S3 → S0, and S0 → S1 transitions, respectively. In these spectra, prominent bands were observed in the symmetric (1300-1450 cm-1) and asymmetric (1500-1600 cm-1) stretching regions of carboxylate groups and in the amide I region (1600-1700 cm-1). Comparison of the band features suggests that the drastic coordination changes of carboxylate groups and the protein conformational changes in the S1 → S2 and S2 → S3 transitions are reversed in the S3 → S0 and S0 → S1 transitions. The flash-induced FTIR measurements during the S-state cycle will be a promising method to investigate the detailed molecular mechanism of photosynthetic oxygen evolution.
  • A Boussac, M Sugiura, Y Inoue, AW Rutherford
    BIOCHEMISTRY 39 (45) 13788 - 13799 0006-2960 2000/11 [Peer-reviewed]
     Scientific journal 
    The Mn-4-cluster and the cytochrome c(550) in histidine-tagged photosystem II (PSII) from Synechococcus elongatus were studied using electron paramagnetic resonance (EPR) spectroscopy. The EPR signals associated with the S-0-state (spin 1/2) and the S-2-state (spin 1/2 and IR-induced spin 5/2 state) were essentially identical to those detected in the non-His-tagged strain. The EPR signals from the S-3-state, not previously reported in cyanobacteria, were detectable both using perpendicular (at g = 10) and parallel (at g = 14) polarization EPR, and these signals are similar to those found in plant PSII. In the Ss-state, near-infrared illumination at 50 K induced a 176-G-wide split signal at a = 2 and signals at g = 5.20 and g = 1.51. These signals differ slightly from those reported in plant PSII [Ioannidis, N,, and Petrouleas, V. (2000) Biochemistry 39, 5246-5254]. In accordance with the cited work, the split signal presumably reflects a radical interacting with the Mn-4-cluster in a fraction of centers, while the g = 5.20 and g 1.51 signals are tentatively attributed to a high-spin state of the Mn-4-cluster with zero field splitting parameters different from those in plant PSII, reflecting minor changes in the environment of the Mn-4-cluster. Biochemical modifications (Sr2+/Ca2+ substitution, acetate and NH3 treatments) were also investigated. In Sr2+-reconstituted PSII, in addition to the expected modified S-2 multiline signal, a signal at g = 5.2 was present instead of the g approximate to 4 signal seen in plant PSII, In NH3-treated samples, in addition to the expected modified S-2-multiline signal, a g approximate to 4 signal was detected in a small proportion of the reaction centers. This is of note since g approximate to 4 spectra arising from the Mn-4-cluster in the S-2 state have not yet been published in cyanobacterial PSII, The detection of modified S-3-signals in both perpendicular (at g = 7.5) and parallel (at g = 12) polarization EPR from NH3-treated PSII indicate that NH3 is still bound in the S-3-state. The acetate-treated PSII behaves essentially as in plant PSII, A study using oriented samples indicated that the heme plane of the oxidized low spin Cytc(550) was perpendicular to the plane of the membrane.
  • T. Noguchi, M. Sugiura
    Biochemistry 39 (36) 10943 - 10949 0006-2960 2000/09 [Peer-reviewed]
     Scientific journal 
    The vibrations of a water molecule in the water-oxidizing complex (WOC) of photosystem II were detected for the first time using Fourier transform infrared (FTIR) spectroscopy. In a flash-induced FTIR difference spectrum upon the S1-to-S2 transition, a pair of positive and negative bands was observed at 3618 and 3585 cm-1, respectively, and both bands exhibited downshifts by 12 cm-1 upon replacement of H216O by H218O. Upon D2O substitution, the bands largely shifted down to 2681 and 2652 cm-1. These observations indicate that the bands at 3618 and 3585 cm-1> arise from the O-H stretching vibrations of a water molecule, probably substrate water, coupled to the Mn cluster in the S2 and S1 states, respectively. The band frequencies indicate that the O-H group forms a weak H-bond and this H-bonding becomes weaker upon S2 formation. Intramolecular coupling with the other O-H vibration of this water molecule was studied by a decoupling experiment using a H2O/D2O (1:1) mixture. The downshifts by decoupling were estimated to be 4 and 12 cm-1 for the 3618 (S2) and 3585 cm-1 (S1) bands, both of which were much smaller than 52 cm-1 of water in vapor, indicating that the observed water has a considerably asymmetric structure i.e., one of the O-H groups is weakly and the other is strongly H-bonded. The smaller coupling in the S2 than the S1 state means that this H-bonding asymmetry becomes more prominent upon S2 formation. Such a structural change may facilitate the proton release reaction that takes place in the later step by lowering the potential barrier. The present study showed that FTIR detection of the O-H vibrations is a useful and promising method to directly monitor the chemical reactions of substrate water and clarify the molecular mechanism of photosynthetic water oxidation.
  • M Sugiura, Y Inoue
    PLANT AND CELL PHYSIOLOGY 40 (12) 1219 - 1231 0032-0781 1999/12 [Peer-reviewed]
     Scientific journal 
    The carboxyl terminus of the CP43 subunit of photosystem II (PSII) in the thermophilic cyanobacterium, Synechococcus elongatus, was genetically tagged with six consecutive histidine residues to create a metal binding site on the PSII supramolecular complex. The histidine-tagging enabled rapid isolation of an intact cyanobacterial PSII core complex from dodecyl maltoside-solubilized thylakoids by a simple one-step Ni2+-affinity column chromatography. The isolated core complex was in a dimeric form with a molecular mass of about 580 kDa, consisting of five major intrinsic membrane proteins (CP47, CP43, D1, D2 and cytochrome b-559), three extrinsic proteins (33 kDa, 12 kDa, and cytochrome c-550), and a few low molecular mass membrane proteins, and evolved oxygen at a rate as high as 3,400 mu mol (mg Chl)(-1) h(-1) at 45 degrees C with ferricyanide as an electron acceptor. The core complex emitted thermoluminescence B-2-, B-1- and Q-bands arising from S(2)Q(B)(-), S(3)Q(B)(-) and S(2)Q(A)(-) charge recombinations at respective emission temperatures of 45, 38 and 20 degrees C, all of which were higher by about 15 degrees C as compared with those in mesophilic spinach BBY membranes. These results indicated that the isolated core complex well retained the intact properties of thermoluminescence of thermophilic cyanobacterial cells, the deeper stabilization of PSII charge pairs. The isolated complex was extremely stable in terms of both protein composition and function, exhibiting no release of extrinsic proteins, no proteolytic degradation in any of its subunits, accompanied by only a slight (less than 10%) loss in oxygen evolution, after dark-incubation at 20 degrees C for 8 d. These properties of the thermophilic PSII core complex are highly useful for various types of studies on PSII.
  • M Sugiura, J Minagawa, Y Inoue
    PLANT AND CELL PHYSIOLOGY 40 (3) 311 - 318 0032-0781 1999/03 [Peer-reviewed]
     Scientific journal 
    A His-tagged PSII core complex was purified from recombinant Chlamydomonas reinhardtii D2-H thylakoids by single-step Ni2+-affinity column chromatography and its properties were partially characterized in terms of their PSII functions and chemical compositions. The PSII core complex that has a His-tag extension at the C-terminus of the D2 protein evolved oxygen at a high rate of 2,400 mu mol (mg Chl)(-1) h(-1) at the optimum pH of 6.5 with ferricyanide and 2,6-dichlorobenzoquinone as electron accepters in the presence of Ca2+ as an essential cofactor, and approximately 90% of the activity was blocked by 10 mu M DCMU. The core complex exhibited the thermoluminescence Q-band but not the B-band regardless of the presence or absence of DCMU, although both bands were observed in the His-tagged thylakoids. The core complex was free from PSI and contained one Y-D, Tyr 160 of the D2 protein, four Mn atoms, two cytochrome b-559, about 46 Chl a molecules, and probably one QA, the primary acceptor quinone of PSII. It was inferred from these results that His-tagging at the C-terminus of the D2 protein does not affect the functional and structural integrity of the PSII core complex, and that the 'His-tag strategy' is highly useful for biochemical, physicochemical, and structural studies of Chlamydomonas PSII.
  • M Sugiura, Y Inoue, J Minagawa
    FEBS LETTERS 426 (1) 140 - 144 0014-5793 1998/04 [Peer-reviewed]
     Scientific journal 
    We have developed a simple and rapid procedure to isolate an oxygen-evolving photosystem II (PS II) core complex from Chlamydomonas reinhardtii. A His-tag made of sis consecutive histidine residues was genetically attached at the carboxy terminus of D2 protein to create a metal binding site on the PS Il supramolecular complex, The recombinant cells producing the His-tagged variant of D2 protein grew photo-autotrophically as well as the wild-type cells. Characterization of the oxygen evolution and the thermoluminescence properties revealed that the His-tagging did not affect the functional integrity of the PS II reaction center. A PS Il core complex was isolated from the detergent-solubilized thylakoids of the recombinant cells in 4 h by a single one-step Ni2+ affinity column chromatography. This preparation consists of D1, D2, CP43, CP47, 33 kDa, and a few low molecular weight proteins, and retains a high rate of oxygen-evolving activity (=1000 mu mol/mg Chl/h), (C) 1998 Federation of European Biochemical Societies.
  • M Sugiura, J Minagawa, Y Inoue
    PHOTOSYNTHESIS: MECHANISMS AND EFFECTS, VOLS I-V 933 - 936 1998 [Peer-reviewed]
     International conference proceedings
  • Miwa Sugiura, Toshiyuki Sakaki, Yoshiyasu Yabusaki, Hideo Ohkawa
    Biochimica et Biophysica Acta - Gene Structure and Expression 1308 (3) 231 - 240 0167-4781 1996/09 [Peer-reviewed]
     Scientific journal 
    A cDNA library constructed from poly(A)+ RNA of tobacco BY2 cells treated with 2,4-dichlorophenoxyacetic acid was screened by using a synthetic oligonucleotide corresponding to the heme binding region of avocado CYP71A1. A cloned 2-kb cDNA designated as cTBP contained an open reading frame of 1593 bp encoding a protein of molecular size of 58916. The deduced amino acid sequence included a cysteine residue corresponding to fifth ligand of heme-Fe at 497th. The coding sequence was expressed under the control of tac promoter and rrnB terminator in Escherichia coli to yield 7 to 10 nmol P450 equivalent per litre of the culture in the presence of 6-aminolevulinic acid. The modified coding sequences in which NH2-terminal residues 2-25 were replaced by the NH2-terminal 18 amino acid residues of microsomal bovine CYP17 were also expressed under the control of ADH promoter and terminator in Saccharomyses cerevisiae to yield 29 and 30 pmol of P450 equivalent/mg protein in the microsomal fraction, respectively. On co-expression of each of the modified coding sequences and yeast NADPH-cytochrome P-450 oxidoreductase gene, the yeast microsomes exhibited 7-ethoxycoumarin O-deethylase activity. Based on these results, tobacco cTBP was found to encode a novel P450-1ike species with a monooxygenese activity related to xenobiotic metabolism.
  • H Ohkawa, N Shiota, H Inui, M Sugiura
    BIOTECHNOLOGY & BIOTECHNOLOGICAL EQUIPMENT 10 (4) 120 - 122 0205-2067 1996 [Peer-reviewed]
     Scientific journal

Books etc

  • 光合成のエネルギー変換と物質変換 〜人工光合成をめざして 光合成研究を支える研究手法「部位特異的変異導入による光化学系の分子構造と機能の解析」
    杉浦 美羽 (Single work)
    化学同人 2015/04
  • 光合成研究と産業応用最前線
    杉浦 美羽 (Single work, 第5章 酸化還元反応 第2節 光合成による高効率エネルギー変換と水の酸化メカニズム)
    エヌティーエス 2014/04
  • 光合成のエネルギー利用と環境応用
    杉浦 美羽 (Single work, 第5章 酸素発生型光合成タンパク質の構造と機能)
    シーエムシー出版 2014/04
  • Photosynthesis and Post-genomic ERA: “From Biophysics to Molecular Biology, a Path in the Research of Photosystem II”参加報告書
    日本光合成研究会 2004
  • FTIR studies on the amino-acid ligands of the photosynthetic oxygen-evolving Mn-cluster
    Waseda University Press 1999
  • FTIR studies on the amino-acid ligands of the photosynthetic oxygen-evolving Mn-cluster
    Waseda University Press 1999
  • Herbicide-resistant tobacco and potate expressing mammalian P450 monooxygenases
    Kluwer Academic Publishers 1997
  • Herbicide-resistant tobacco and potate expressing mammalian P450 monooxygenases
    Kluwer Academic Publishers 1997

Conference Activities & Talks

  • The role of Valine 185 of the D1 protein in the Photosystem II oxygen evolution  [Not invited]
    The role of Valine, of the, rotein in the Photosystem II oxygen evolution, Miwa Sugiura, Itsuki Takachi, Yuya Hara, Shin Kanawaku, Julien Sellés, Alain Boussac
    Third International Solar Fuels Conference / International Conference on Artificial Photostnthesis-2019  2019/11
  • X-Ray crystallographic analysis of Photosystem II from a PsbA2-only strain and its complex with bromoxynil  [Not invited]
    Naoki Tone, Natsumi Ugai, Yoshiki Nakajima, Michihiro Suga, Fusamichi Akita, Yasufumi Umena, Akiko Nakagawa, Miwa Sugiura, Jian-Ren Shen
    Third International Solar Fuels Conference / International Conference on Artificial Photostnthesis-2019  2019/10
  • ChlD1の異なるリガンド構造がP680の機能にもたらす影響  [Not invited]
    島本直拓, 中村誠, 竹川裕紀, 杉浦美羽
    第10回日本光合成学会年会  2019/05
  • 光化学系IIアクセサリークロロフィルの軸配位子環境と強光との関係  [Not invited]
    木村仁哉, 中村誠, 竹川裕紀, 杉浦美羽
    第10回日本光合成学会年会  2019/05
  • New Insights on ChlD1 Function in PhotosystemⅡ from Site-Directed Mutants  [Invited]
    Miwa Sugiura
    10th OCARINA International Symposium  2019/03
  • 光化学系II複ヘムタンパク質Cytb559の異なるリガンドが及ぼす機能と構造への影響  [Not invited]
    杉浦美羽, 中村誠, Alain Boussac, 梅名康史, 沈建仁
    第2回新学術領域「革新的光-物質変換」公開シンポジウム  2019/01
  • 光化学系IIのP680クロロフィルのリガンド環境と光合成機能との関係  [Invited]
    杉浦 美羽
    第2回新学術領域「革新的光-物質変換」公開シンポジウム  2019/01
  • X-ray crystallographic analysis of Photosystem II from a PsbA2-only strain and its complex with herbicides  [Not invited]
    Naoki Tone, Takahiro Kuma, Yoshiki Nakajima, Michihiro Suga, Fusamichi Akita, Yasufumi Umena, Akiko Nakagawa, Miwa Sugiura, Jian-Ren Shen
    International Symposium on Photosynthesis and Chloroplast Biogenesis 2018  2018/11
  • Molecular Mechanisms of Efficient Electron Transfer and Water Oxidation in Photosystem II  [Invited]
    Miwa Sugiura
    1st Evolutionary Materials Workshop in Seoul National University  2018/10
  • 光合成による高効率エネルギー変換機構の理解と応用研究はどこまで進んだか?  [Invited]
    杉浦 美羽
    平成30年度日本農芸化学会西日本支部大会 シンポジウム「限りある資源、地球環境への農芸化学からの取り組み」  2018/09
  • 光化学系IIの水の酸化反応におけるD1/V185の役割について  [Not invited]
    高智五輝, 原侑也, Alain Boussac, 杉浦美羽
    第56回日本生物物理学会年会  2018/09
  • Role of accessory chlorophyll ChlD1 as P680 in Photosystem II  [Invited]
    Miwa Sugiura
    1st Asia-Oceania International Congress on Photosynthesis  2018/08
  • 光化学系IIの水の酸化反応におけるD1-V185の役割の解明  [Not invited]
    第9回日本光合成学会年会  2018/05
  • 光化学系IIを構成するCyb559のヘム周辺構造の変化がアクセプター側へ及ぼす影響  [Not invited]
    中村誠, Alain Boussac, 杉浦美羽
    第9回日本光合成学会年会  2018/05
  • 光化学系IIにおけるP680アクセサリークロロフィル軸配位子の構造変化がもたらす機能への影響  [Invited]
    杉浦 美羽
    第1回新学術領域「革新的光-物質変換」公開シンポジウム  2018/01
  • New insights in PSII functions from the study of donor side and acceptor side mutants.  [Invited]
    Miwa Sugiura
    France-Japan Joint Workshop on the Structure and Function of Photosystem II  2017/12
  • Effects of the ligand modification of the ChlD1 on the Photosystem II photochemistry  [Not invited]
    Yuki Takegawa, Alain Boussac, Miwa Sugiura
    Japan-France Joint Workshop on the Structure and Function of Photosystem II  2017/12
  • The binding of herbicides to the different Photosystem II variants.  [Not invited]
    Itsuki Takachi, Miwa Sugiura
    Japan-France Joint Workshop on the Structure and Function of Photosystem II  2017/12
  • Structural modifications of Cytb559 and their effects on its redox properties  [Not invited]
    Makoto Nakamura, lain Boussac, Miwa Sugiura
    Japan-France Joint Workshop on the Structure and Function of Photosystem II  2017/12
  • Redox property changes of cytochrome b559 of site-directed mutants in Photosystem II complex  [Not invited]
    Makoto Nakamura, Alain Boussac, Miwa Sugiura
    Protein Island Matsuyama International Symposium  2017/10
  • Binding Properties of Herbicides to Photosystem II complex of Thermosynechococcus elongatus  [Not invited]
    Itsuki Takachi, Miwa Sugiura
    Protein Island Matsuyama International Symposium  2017/09
  • Effects of Different Ligand of Accessory Chlorophyll, ChlD1, of the Primary Electron Donor P680 in Photosystem II on Energy Dynamics  [Not invited]
    Yuki Takegawa, Miwa Sugiura
    Protein Island Matsuyama International Symposium  2017/09
  • 部分構造の異なるD1タンパク質で構成されたThermosynechococcus elongatus光化学系IIへの除草剤結合の比較  [Not invited]
    高智五輝, 杉浦美羽
    第8回日本光合成学会年会  2017/05
  • 光化学系IIの一次電子供与体P680を構成するChlD1軸配位子と機能との関係  [Not invited]
    竹川裕紀, Alain Boussac, 杉浦美羽
    第8回日本光合成学会年会  2017/05
  • 光化学系IIにおけるCyb559ヘム周辺アミノ酸の部位特異的変異によるレドックス変化  [Not invited]
    中村誠, Alain Boussac, 杉浦美羽
    第8回日本光合成学会年会  2017/05
  • Influence of molecular structural modification of Cytb559 on Photosystem II function  [Not invited]
    Makoto Nakamura, Boussac Alain, Miwa Sugiura
    第58回日本植物生理学会年会  2017/03
  • Molecular function and structure of Photosystem II in photosynthetic electron transfer  [Invited]
    Miwa Sugiura
    Solar Fuel Material –Maltiscale and Bioinspired Approach in Catalyst-  2017/02
  • 光合成による高効率エネルギー変換と水の酸化機構の解明  [Invited]
    杉浦 美羽
    第7回「フォーラム:人工光合成」  2017/01
  • 光化学系IIによる水の酸化と電子移動の分子機構  [Invited]
    杉浦 美羽
    重点課題5 第3回公開シンポジウム  2016/12
  • Time-resolved infrared analysis of the S0-to-S1 transition of  [Not invited]
    Tatsuki Shimizu, Miwa Sugiura, Takumi Noguchi
    GER International Symposium on Science of Molecular Assembly and  2016/09
  • Assembly of oxygen-evolving Photosystem II efficiently occurs with the apo-Cytb559 but the holo-Cytb559 accelerates the recovery of a functional enzyme upon photoinhibition  [Not invited]
    Miwa Sugiura, Makoto Nakamura, Alain Boussac
    The 17th International Congress on Photosysntheses Research  2016/08
  • Role of D1-Pro173 of Photosystem II in Water Oxidation  [Invited]
    Miwa Sugiura
    7th International Conference Photosynthesis Research for Sustainability-2016  2016/06
  • 光化学系II複合体で表面修飾された層状複水酸化物電極による水の光酸化  [Not invited]
    加藤 優, 佐藤久子, 杉浦美羽, 八木一三
    2015年電気化学会第83回大会  2016/03  大阪大学
  • 光合成による高効率エネルギー変換と水の酸化機構の解明  [Invited]
    杉浦 美羽
    JST第6回「フォーラム:人工光合成」〜人工光合成研究の課題と展望〜  2016/03
  • Crystal structure of herbicide-bound PsbA3-only photosystem II  [Not invited]
    Takahiro Kuma, Fusamichi Akita, Natsumi Ugai, Michihiro Suga, Miwa Sugiura, Masako Iwai, Masahiko Ikeuchi, Jian-Ren Shen
    第57回日本植物生理学会年会  2016/03  岩手大学
  • 光化学系II複合体 Cytb559の構造変化による光阻害への影響  [Not invited]
    Makoto Nakamura, Alain Boussac, Miwa Sugiura
    第57回日本植物生理学会年会  2016/03  岩手大学
  • 光合成のエネルギー変換と物質変換:光合成の理解と応用研究はどこまで進んだか?  [Invited]
    杉浦 美羽
    マリンバイオテクノロジー学会  2015/11  東京大学 
    「若手の会シンポジウム」
  • Molecular structure relating to rate of water oxidation and electrontransfer in Photosystem II  [Invited]
    Miwa Sugiura
    The 7th Asia and Oceania Conference on Photobiology  2015/11
  • Effects of Structural Modification around TyrZ and D1-His190 on Proton-coupled Electron Transfer in Photosystem II  [Invited]
    Miwa Sugiura
    International Symposium 2015- Protonation Dynamics in Redox Proteins  2015/09
  • Engineered Themosynechococcus elongatus mutant growing under photoheterotrophic conditions  [Invited]
    Miwa Sugiura
    Gordon Research Conference: Photosynthesis: The Dynamics and Regulation of Photosynthesis: From the Origin of Biocatalysis to Innovative Solar Conversion  2015/06
  • PsabA3のみを発現させたPsbA3-PSII の1.9 Å 分解能での結晶構造  [Not invited]
    鵜飼奈津美, 菅倫寛, 杉浦美羽, 岩井雅子, 池内昌彦, 沈建仁
    第6回日本光合成学会年会  2015/05  岡山国際交流センター
  • 光化学系IIの水の酸化過程で生じるプロトン排出経路に関する研究  [Not invited]
    谷口智紀, 杉浦美羽
    第6回日本光合成学会年会  2015/05  岡山国際交流センター
  • Thermosynechococcus elongatus由来の特徴のあるPsbA2-PSIIの分子構造解析の試み  [Not invited]
    中川彰子, 菅倫寛, 鵜飼奈津美, 沈建仁, 杉浦美羽
    第6回日本光合成学会年会  2015/05  岡山国際交流センター
  • Two new c-type cytochromes found in cyanobacteria: Tll0287 and PsbV2  [Not invited]
    Thanh-Lan Lai, Miwa Sugiura, Frauke Baymann, Wolfgang Nitschke, Fabrice Rappaport, Alain Desbois
    French Photosynthesis Society  2015/05
  • 光合成による高効率エネルギー変換と水の酸化機構の解明  [Not invited]
    杉浦美羽
    第3回 JSTさきがけ「光エネルギーと物質変換」研究成果報告会「人工光合成研究の最前線:挑戦する若手研究者」  2015/03  日本大学理工学部船橋キャンパス
  • 杉浦美羽
    第95回日本化学会春期年会  2015/03 
    特別企画「バイオ超分子が拓く驚異の物質科学」
  • 杉浦美羽
    日本生体エネルギー研究会 第40回討論会  2014/12 
    シンポジウム「バイオエナジェティクスと産業利用」
  • The D1-173 amino acid plays a key role in the structure-function relationship of TyrZ and D1-His190 in Photosystem II  [Invited]
    Miwa Sugiura
    8th International Symposium on Nanomedicine  2014/12
  • Thermophilic Cyanobacterium Thermosynechococcus elongatus Mutant Acquired The Photo-heterotorophic Growth Capacity  [Not invited]
    Masato Nakamura, Miwa Sugiura
    8th International Symposium on Nanomedicine  2014/12
  • Influence on Photoinhibition by the Structural Modification of Cytb559 in PhotosystemII Complex  [Not invited]
    Makoto Nakamura, Alain Boussac, Miwa Sugiura
    8th International Symposium on Nanomedicine  2014/12
  • Comparison of The Binding Manner of Herbicides in Photosystem II Composed of D1 Variants in Thermosynechococcus elongatus  [Not invited]
    Akiko Nakagawa, Miwa Sugiura
    8th International Symposium on Nanomedicine  2014/12
  • 光合成に使われている色素を取り出してみよう!  [Invited]
    杉浦 美羽
    平成26年度愛媛未来づくり共同提案事業 実験サイエンスカフェ for girls  2014/11
  • Environment of TyrZ in Photosystem II from Thermosynechococcus elongatus in which PsbA2 is the D1 protein  [Not invited]
    Miwa Sugiura, Shogo Ogami, Fabrice Rappaport, Alain Boussac
    2014 International Conference on Artificial Photosynthesis  2014/11
  • 幸せな人生を送るための人生設計と今やっておくこと 〜研究者になった私の例を挙げて〜  [Invited]
    杉浦 美羽
    平成26年度中高生のためのキャリアデザイン講座  2014/10
  • 層状複水酸化物修飾電極を用いた光化学系IIの光電気化学  [Not invited]
    加藤優, 佐藤久子, 杉浦美羽
    電気化学会秋季年会  2014/09  北海道大学
  • 光化学系II複合体と層状複水酸化物からなるバイオー無機ハイブリッド電極  [Not invited]
    加藤優, 佐藤久子, 杉浦美羽
    第52回 日本生物物理学会年会  2014/09  札幌コンベンションセンター
  • 光合成による高効率エネルギー変換機構と光合成太陽電池の開発  [Invited]
    杉浦 美羽
    日本電熱学会 第26回中四国電熱セミナー  2014/09
  • High Efficient Energy Conversion by Photosynthesis and its Application to Bio-photovoltaics.  [Invited]
    Miwa Sugiura
    The 12th Japan-America Frontiers of Engineering Symposium  2014/06
  • Histidine Hydroxyl Modification on D2-His336 in Photosystem II of Thermosynechoccocus vulcanus and Thermosynechoccocus elongatus.  [Invited]
    Miwa Sugiura
    International Meeting “Photosynthesis Research for Sustainability – 2014"  2014/06
  • 食材の安全性について考える〜遺伝子組換え作物と農薬について〜  [Invited]
    杉浦 美羽
    国際ソロプチミスト松山  2014/04
  • High efficient energy conversion by photosynthesis and its application to bio-photovoltaics.  [Invited]
    Miwa Sugiura
    第12回日米先端工学(JAFOE)シンポジウム事前勉強会  2014/04
  • 光合成光化学系IIの水の酸化速度を制御するPCET  [Not invited]
    杉浦美羽
    第4回フォーラム「人工光合成」-JSTさきがけ研究・新学術領域研究の学術発信と研究者への期待-  2014/03  名古屋大学
  • 愛媛大学でのサイエンスカフェの取り組み  [Invited]
    杉浦 美羽
    高知大学農学部  2014/03
  • 光合成による高効率エネルギー変換と水の酸化機構の解明  [Invited]
    杉浦 美羽
    JSTさきがけ「光エネルギーと物質変換」領域研究成果報告会:人工光合成研究の最前線 -挑戦する若手研究者-  2014/03
  • Efficient Photosynthetic Electron Transfer and Water Oxidation in Photosystem II  [Invited]
    Miwa Sugiura
    7th International Symposium on Nanomedicine  2013/11
  • 水の光分解を目指した光化学系IIを有する酸化物電極の開発  [Not invited]
    加藤優, 佐藤久子, 杉浦美羽
    日本化学会低次元系光機能材料研究会 第2回サマーセミナー  2013/09  松山
  • Photoelectrochemical water oxidation using Photosystem II integrated electrodes  [Not invited]
    Masaru Kato, Miwa Sugiura
    Protein Island Matsuyama International Symposium  2013/09
  • Construction of thermophilic cyanobacterium mutant which grow photoautotroph  [Not invited]
    Masato Nakamura, Miwa Sugiura
    Protein Island Matsuyama International Symposium  2013/09
  • Efficiency of photosynthesis is controlled by environments of molecular structure around cofactors relating to electron transport and water oxidation in Photosystem II  [Not invited]
    Miwa Sugiura
    Protein Island Matsuyama International Symposium  2013/09
  • Environment of TyrZ in Photosystem II from Thermosynechococcus elongatus in which PsbA2 Is the D1 Protein  [Invited]
    Miwa Sugiura, Shogo Ogami, Mai Kusumi, Sun Un, Fabrice Rappaport, Alain Boussac
    The 16th International Congress of Photosynthesis  2013/08
  • Molecular structures relating regulation of electron transfer in Photosystem II  [Invited]
    Miwa Sugiura
    International Conference of "Photosynthesis Research for Sustainerbility-2013", Baku, Azerbaijan  2013/06
  • 光合成光化学系IIの水の酸化速度を制御するPCET  [Not invited]
    杉浦美羽, Fabrice Rappaport, Alain Boussac
    JSTさきがけ「光エネルギーと物質変換」研究領域第1期採択研究者研究成果報告会・研究成果発表会「人工光合成研究の最前線:挑戦する若手研究者」  2013/03  立命館大学びわこ・くさつキャンパス
  • エネルギー問題って? 新エネルギー技術を紹介、解説します。  [Invited]
    杉浦 美羽
    サイエンスカフェ@愛大 〜環境・エネルギー問題に挑む新テクノロジー〜  2013/03
  • Regulation of electron transfer in Photosystem II  [Invited]
    Miwa Sugiura
    2012 OCARINA Annual International Meeting -Launch of the Artificial Photosynthesis Research Center-  2013/03
  • 光化学系IIの電子伝達制御機構  [Invited]
    杉浦 美羽
    第54回日本植物生理学会年会 シンポジウム「光化学系Ⅱによる水分解・酸素発生反応の分子機作」  2013/03
  • 社会ニーズにおける光合成研究  [Invited]
    杉浦 美羽
    日本女性科学者の会 新春懇談会  2013/01
  • 光化学系IIの電子伝達制御に関わる構造環境  [Invited]
    杉浦 美羽
    第85回日本生化学会大会 シンポジウム「精密構造に基づく生体光エネルギー変換の分子機構」  2012/12
  • Photosystem II complexes composed of different D1 variants  [Invited]
    Miwa Sugiura
    6th International Symposium on Nanomedicine  2012/11
  • Overview of structure and function of PSII  [Invited]
    Miwa Sugiura
    10th International Plant Molecular Biology Congress  2012/10
  • Hetrotrophicaly growable thermophilic cyanobacterium Thermosynechococcus elongatus  [Not invited]
    Masato Nakamura, Miwa Sugiura
    10th International Plant Molecular Biology Congress  2012/10
  • Mechanism of controlling the redox potentials of the quinone electron acceptors in photosystem II  [Not invited]
    Ryota Ashizawa, Takuya Iwasa, Miwa Sugiura, Takumi Noguchi
    第50回 日本生物物理学会年会  2012/09  名古屋大学
  • サイエンス分野における男女共同参画 〜理系女子のキャリアデザイン〜  [Invited]
    杉浦 美羽
    平成24年度 第17回 男女参画社会づくり推進県民大会  2012/06
  • 光合成エネルギー変換機構の解明へ導く光化学系II反応中心タンパク質を欠損させた好熱性ラン藻の構築  [Not invited]
    中村優斗, 杉浦美羽
    日本生物物理学会 第4回 中国四国支部大会  2012/06  山口大学
  • PCETに制御される光化学系IIの水の酸化過程  [Not invited]
    杉浦美羽, 大上翔悟, 楠見真依, Fabrice Rappaport, Alain Boussac
    日本生物物理学会 第4回 中国四国支部大会  2012/06  山口大学
  • 光合成による水の酸化速度と電子伝達コファクターとの関係  [Not invited]
    杉浦美羽
    さきがけ4領域合同国際シンポジウム  2012/03  慶應義塾大学
  • 酸素発生複合体におけるCa2+/Sr2+およびCl-/Br-置換が光化学系IIのエナジェティックスに及ぼす影響  [Not invited]
    山本 昌一, 芝本 匡雄, 加藤 祐樹, 杉浦 美羽, Alain Boussac, 渡辺 正
    第53回 日本植物生理学会年会  2012/03  京都産業大学
  • Energy Conversion by Photosystem II and application to energy creation  [Invited]
    Miwa Sugiura, Michele Vittadello, Paul. G. Falkovski, Alain Boussac
    5th International Symposium on Nanomedicine  2012/03
  • Thermosynechococcus elongatusの部分構造の異なったD1タンパク質で構成される光化学系IIの機能と構造の比較  [Invited]
    杉浦 美羽
    平成23年度 大阪市立大学複合体先端研究機構 年次総会  2012/03
  • Energetic comparison of Thermosynechococcus elongatus Photosystem II composed of either PsbA1 or PsbA3  [Not invited]
    Miwa Sugiura, Fabrice Rappaport, Yuki Kato, Takumi Noguchi, Alain Boussac
    第50回 日本生物物理学会年会  2011/09  兵庫県立大学
  • 光合成研究の最前線と課題  [Invited]
    杉浦 美羽
    第50回 日本生物物理学会年会 シンポジウム「光合成研究で何が明らかにされ、これから何をできるか? 〜光合成研究の最先端とエネルギー創製研究の現状〜  2011/09  兵庫県立大学
  • 光合成によるエネルギー変換のしくみと新エネルギー創製への応用  [Invited]
    杉浦 美羽
    第2回 愛媛大学学術フォーラム  2011/07  愛媛大学
  • 光合成の高効率エネルギー変換機構と新エネルギー創製への応用  [Invited]
    杉浦 美羽
    日本学術振興会 産学協力研究委員会・分子系の複合電子機能第181委員会・第11回研究会「人工光合成ー分子・生体系」  2011/07  東京工業大学
  • Comparison of Thermosynechococcus elongatus PSII composed of different D1  [Invited]
    杉浦 美羽
    International Conference of "Photosynthesis Research for Sustainerbility", Baku, Azerbaijan  2011/07
  • 光化学系II複合体の電子伝達と光の電気エネルギーへの変換  [Not invited]
    杉浦 美羽, Michel Vittadello, Paul G. Falkovski
    ナノ学会 第9回大会  2011/06  北海道大学
  • 光化学系II複合体における小サブユニットタンパク質の役割  [Not invited]
    杉浦美羽, 原田紗代, 岩井恵理
    第3回 生物物理学会中四国支部大会  2011/05  広島大学
  • Structural stability of Photosystem II complex composed of either PsbA1 or PsbA3  [Not invited]
    Miwa Sugiura, Yuki Kato, Alain Boussac
    第49回 日本生物物理学会年会  2011/05  東北大学
  • 光合成によるエネルギー変換と水の酸化機構  [Invited]
    杉浦 美羽
    ”2011世界化学年”記念 JST さきがけ研究領域合同シンポジウム「人類の危機に挑む研究開発:光と太陽エネルギー」  2011/03  神奈川大学
  • 部分構造の異なる反応中心タンパク質D1で構成される光化学系IIのエナジェティクスの違い  [Invited]
    杉浦 美羽
    大阪大学蛋白質研究所セミナー「分子科学と生理学が解き明かす植物の光エネルギー変換の新展開」  2011/03  大阪大学蛋白質研究所
  • Recent progress in Photosystem II research using mutagenesis of Thermosynechococcus elongatus,  [Invited]
    Miwa Sugiura
    Japanese-Finnish Seminar 2011 Future prospects of photosynthetic organisms: from genomes to environment  2011/03
  • Overview of Photosystem II and artificial photosynthesis research  [Invited]
    SUGIURA Miwa
    The 70th Okazaki International Conference  2010/12
  • Molecular structure and function of Thermosynechococcus elongatus Photosystem II composed of either D1:1 or D1:3  [Invited]
    Miwa Sugiura, Fabrice Rappaport, Yuki Kato, Takumi Noguchi, Alain Boussac
    The 15th International Congress of Photosynthesis  2010/08  Beijing, China
  • Energetics within photosystem II based on the redox potentials of pheophytin a and primary quinone QA determined by spectroelectrochemistry  [Not invited]
    Yuki Kato, Miwa Sugiura, Tadashi Watanabe
    Molecular Basis of Photosynthetic Energy and Electron Transfer and Related Respiratory Processes ~Satellite Meeting  2010/08
  • Evidence that D1-His332 in Photosystem II from Thermosynechococcus elongatus interacts with the S3-state and not with the S2-state  [Not invited]
    Miwa Sugiura, Fabrice Rappaport, Warwick Hillier, Pierre Dorlet, Alain Boussac
    Molecular Basis of Photosynthetic Energy and Electron Transfer and Related Respiratory Processes ~Satellite Meeting  2010/08
  • Spectroelectrochemical determination of the redox potentials of electron acceptors, pheophytin a and primary quinone QA, in photosystem II  [Not invited]
    Yuki Kato, Tadao Shibamoto, Akinori Oda, Miwa Sugiura, Tadashi Watanabe
    The 15th International Congress of Photosynthesis  2010/08
  • 分光電気化学法による光化学系II電子受容分子の酸化還元電位計測  [Not invited]
    加藤祐樹, 芝本匡雄, 杉浦美羽, 渡辺正
    第37回生体分子科学討論会  2010/06  山口大学
  • 光化学系II複合体タンパク質の分子構造と機能の関係  [Invited]
    杉浦 美羽
    2010年 ナノ学会第8回大会 未来を拓くナノサイエンス:理学、工学、医学への広がり  2010/05
  • Recent progress of research in molecular mechanism and structure of Photosystem II complex  [Invited]
    Miwa Sugiura
    Seminar in National Institute for Genetics  2010/04
  • 1064 nm 励起顕微ラマン分光法によるシアノバクテリアのin vivo測定  [Not invited]
    安藤正浩, 杉浦美羽, 林秀則, 浜口宏夫
    第90回 日本化学会春季年会  2010/03  近畿大学
  • 分光電気化学計測による光化学系II電子伝達分子のエネルギー準位相関の解明  [Not invited]
    加藤 祐樹, 芝本 匡雄, 杉浦 美羽, 渡辺 正
    第90回 日本化学会春季年会  2010/03  近畿大学
  • Thermosynechococcus elongatusの光化学系II一次電子受容体フェオフィチンaの酸化還元電位: コアタンパク質D1:1とD1:3の違いが電位に及ぼす影響について  [Not invited]
    加藤祐樹, 杉浦美羽, 渡辺 正
    第51回 日本植物生理学会年会  2010/03  熊本大学
  • 分光電気化学的手法による光化学系II第一キノン電子受容体QAの酸化還元電位計測  [Not invited]
    芝本匡雄, 加藤祐樹, 杉浦美羽, 渡辺 正
    第51回 日本植物生理学会年会  2010/03  熊本大学
  • 光化学系IIにおけるチロシンYZとD1-H190の相互作用  [Not invited]
    高橋亮太, 杉浦美羽, Alain Boussac, 野口巧
    第51回 日本植物生理学会年会  2010/03  熊本大学
  • Psb30はPSII複合体において構造の安定保持を担う  [Not invited]
    原田紗代, Alain Boussac, 林秀則, 杉浦美羽
    第51回 日本植物生理学会年会  2010/03  熊本大学
  • D1:1とD1:3で構成されるThermosynechococcus elongatusの光化学系II複合体の分子構造と機能の比較  [Not invited]
    杉浦美羽, Fabrice Rappaport, 加藤祐樹, Alain Boussac
    第51回 日本植物生理学会年会  2010/03  熊本大学
  • 異なるアミノ酸を持つ反応中心タンパク質で構成される光化学系II複合体のエネルギー論的な比較  [Not invited]
    杉浦美羽, Fabrice Rappaport, 加藤祐樹, Alain Boussac
    日本生体エネルギー研究会第35回討論会  2009/12  旭川医科大学
  • 異なる反応中心D1タンパク質で構成された光化学系II複合体タンパク質の分子構造と光合成機能  [Invited]
    杉浦 美羽
    2009年 日本化学会西日本大会  2009/11
  • QA再構成とFTIR解析によるPSIIにおける第一電子受容体QAの分子間相互作用の解析  [Not invited]
    梢雄多, 高野晃, 杉本育代, 鈴木博行, 杉浦美羽, 高橋裕一郎, 野口巧
    第47回生物物理学会年会  2009/10  アスティ徳島
  • 分光電気化学的手法により計測した光化学系IIフェオフィチンaの酸化還元電位  [Not invited]
    加藤祐樹, 杉浦美羽, 渡辺正
    第47回生物物理学会年会  2009/10  アスティ徳島
  • 好熱性ラン藻のD1:3は恒常的に発現しているD1:1よりも安定な光化学系II複合体を構成する  [Not invited]
    杉浦美羽, 原田紗代, 岩井恵理, 真鍋敬, 林秀則, Alain Boussac
    第47回生物物理学会年会  2009/10  アスティ徳島
  • Recent Progress in the Photosytem II enzyme  [Invited]
    杉浦 美羽
    Seminar in CEA Saclay, Service de Bioénergétique, Biologie Structurale et Mécanismes(invited by Dr. Alain Boussac)  2009/09
  • Affinity of structurally modified metalothionein to heavy metals  [Not invited]
    Shin-ichi Takeuchi, Miwa Sugiura, Hidenori Hayashi
    The 14th International Conference on Biological Inorganic Chemistry  2009/07
  • FTIR detection of the DOD bending vibrations of water molecules involved in the photosynthetic water oxidation  [Not invited]
    Hiroyuki Suzuki, Miwa Sugiura, Takumi Noguchi
    he 14th International Conference on Biological Inorganic Chemistry  2009/07
  • Hydrogen bond network around the non-heme iron in Photosystem II  [Not invited]
    Ryouta Takahashi, Miwa Sugiura, Alain Boussac, Takumi Noguchi
    The 14th International Conference onBiological Inorganic Chemistry  2009/07
  • Metallothioneins expressed in the lumen and stroma of thylakoids of a thermophilic cyanobacterium Thermosynechococcus elongatus  [Not invited]
    Hiroshi Nakano, Takashi Manabe, Hidenori Hayashi, Miwa Sugiura
    The 14th International Conference onBiological Inorganic Chemistry  2009/07
  • Structural and mechanistic investigations in the Photosystem II oxygen evolving enzyme upon exchanges of Br- for Cl- and Sr2+ for Ca2+.  [Not invited]
    Alain Boussac, Naoko Ishida, Thanh-Lan Lai, A. William Rutherford, Pierre Dorlet, Katrin Beckman, Johannes Messinger, Yulia Pushkar, Junko Yano, Jan F. Kern, Vittal K. Yachandra, Fabrice Rappaport, Miwa Sugiura
    The 14th International Conference onBiological Inorganic Chemistry  2009/07
  • Influence of D1-H332, a ligand to the Mn4Ca-cluster, in the water oxidation mechanism of the oxygen-evolving Photosystem II enzyme  [Not invited]
    Miwa Sugiura, Yohei Ohno, Fabrice Rappaport, Hiroyuki Suzuki, Takumi Noguchi, Hidenori Hayashi, Alain Boussac
    The 14th International Conference on Biological Inorganic Chemistry  2009/07
  • Synechococcus sp. PCC 7002のZn2+ストレス応答における転写因子SmtBによる遺伝子発現調節  [Not invited]
    相原加奈子, 杉浦美羽, 林秀則
    第50回 日本植物生理学会年会  2009/03  名古屋大学
  • 光化学系Ⅱコア蛋白質における第一キノン電子受容体QAの再構成  [Not invited]
    梢雄多, 高野晃, 鈴木博行, 杉浦美羽, 野口巧
    第50回 日本植物生理学会年会  2009/03  名古屋大学
  • 光合成水分解反応の赤外分光解析:DOD変角振動による水分子の検出  [Not invited]
    鈴木 博行, 杉浦美羽, 野口巧
    第50回 日本植物生理学会年会  2009/03  名古屋大学
  • 分光電気化学的手法によるThermosynechococcus elongatus由来の光化学系II一次電子受容体フェオフィチンaの酸化還元電位計測  [Not invited]
    加藤祐樹, 杉浦美羽, 渡辺 正
    第50回 日本植物生理学会年会  2009/03  名古屋大学
  • 水の酸化反応におけるD1-His332の役割  [Not invited]
    杉浦美羽, 大野陽平, Alain Boussac, Fabrice Rappapor, 鈴木博行, 野口巧, 林秀則
    第50回 日本植物生理学会年会  2009/03  名古屋大学
  • Energy conversion efficiency by Photosystem II assembled with variant copies of subunit D1 in themophilic cyanobacterium Themosynechococcus elongatus  [Not invited]
    Miwa Sugiura, Fabrice Rappaport, Alain Boussac
    Woody Plants Biotechnology Symposium, Nissan Science Foundation  2009/02
  • 光化学系IIタンパク質複合体の分子構造の解析の現状  [Invited]
    杉浦 美羽
    2008年度 愛媛地区分析化学講演会  2009/01
  • 光化学系IIにおける水の分解メカニズム  [Invited]
    杉浦 美羽
    2008年度 日本化学会 中国四国支部会  2008/12
  • The water splitting enzyme: recent advances  [Not invited]
    A Boussac, N Ishida, T-L lai, AW Rutherford, F Rappaport, Y Pushkar, M Sugiura
    第46回 日本生物物理学会 シンポジウム〜光合成の新たなる潮流〜  2008/12  福岡国際会議場
  • 光化学系IIの構造と機能の解明から応用まで  [Invited]
    杉浦 美羽
    第46回 日本生物物理学会年会 シンポジウム「光合成の新たなる潮流=光合成で新エネルギー創成を達成できるか=」  2008/12
  • Ycf12 (Psb30)はSynechocystis 6803光化学系IIの構成サブユニットである  [Not invited]
    井上名津子, 高橋武志, 伴亜希子, 杉浦美羽, 高橋裕一郎, 菓子野康浩, 佐藤和彦
    第72回日本植物学会年会  2008/09  高知大学
  • Effects of P680 ligand substitution in the oxygen-evolving Photosystem II of Thermosynechococcus elongatus  [Not invited]
    Miwa Sugiura, Alain Boussac, Takumi Noguchi, Fabrice Rappaport
    Protein Island Matsuyama Inernational Symposium  2008/08
  • 酸素発生型光合成微生物による光ー水素生成  [Invited]
    杉浦 美羽
    2008年度(社)関西電子工業振興センターセミナー:新エネルギー開発の現状と将来  2008/07
  • 光合成水分解系における水分子の反応:D2O変角振動の赤外分光検出  [Not invited]
    鈴木博行, 杉浦美羽, 野口巧
    日本光合成研究会  2008/05  名古屋大学
  • ゲノム情報のない生物における膜タンパク質の同定ーD1タンパク質を例として  [Not invited]
    菓子野康浩, 井上名津子, 杉浦美羽, 佐藤和彦
    第49回日本植物生理学会年会  2008/03  札幌コンベンションセンター
  • 光化学系IIにおけるチロシンYDと水分子の相互作用  [Not invited]
    高橋亮太, 杉浦美羽, 野口巧
    第49回日本植物生理学会年会  2008/03  札幌コンベンションセンター
  • FTIR法による光合成水分解反応におけるプロトン放出パターンの検出  [Not invited]
    鈴木博行, 杉浦美羽, 野口巧
    第49回日本植物生理学会年会  2008/03  札幌コンベンションセンター
  • 分子の視点から見る光合成  [Invited]
    杉浦 美羽
    分子科学研究所セミナー  2008/03
  • Molecular Structure and Function of Photosytem II  [Invited]
    Miwa Sugiura
    International Seminar of “Photosynthesis” in Kwansei-gakuin University (invited by Professor Yasushi Koyama)  2007/12
  • Structural coupling of water molecules with YD in Photosystem II as revealed by FTIR spectroscopy  [Not invited]
    Ryota Takahashi, Miwa Sugiura, Takumi Noguchi
    The 14th International Congress on Photosynthesis  2007/07
  • FTIR study on the proton release pattern duing water oxidation in Photosystem II core complexes from Thermosynechococcus elongatus  [Not invited]
    Hiroyuki Suzuki, Miwa Sugiura, Takumi Noguchi
    The 14th International Congress on Photosynthesis  2007/07
  • Spectroscopic studies of the Mn4Ca cluster in mutants and biosyntheticallt modified Photosystem II from Thermosynechococcus elongatus  [Not invited]
    Alain Boussac, Miwa Sugiura, Naoko Ishida, Sun Un, Fabrice Rappaport, A. William Rutherford
    The 14th International Congress on Photosynthesis  2007/07
  • 光合成酸素発生マンガンクラスターにおけるCa2+イオン近傍の構造  [Not invited]
    鈴木博行, 渋谷勇一, 田口雄太, 杉浦美羽, Alain Boussac, 野口巧
    第34回 生体分子討論会  2007/06  東北大学
  • 光化学系IIにおけるチロシンYDの水素結合構造と水分子との相互作用  [Not invited]
    高橋亮太, 杉浦美羽, 野口巧
    日本光合成研究会  2007/05  岡山大学
  • 光合成水分解反応のS状態サイクルにおけるプロトン放出パターン:FTIR法による解  [Not invited]
    鈴木博行, 杉浦美羽, 野口巧
    日本光合成研究会  2007/05  岡山大学
  • Spectroscopic studies of the Mn4Ca cluster in mutants and biosynthetically modified Photosystem II from Thermosynechococcus elongatus  [Invited]
    Alain Boussac, Miwa Sugiura
    Royal Society meeting: How Nature uses sunlight to split water  2007/04  London, England
  • 光化学系ⅡにおけるチロシンYDの水素結合構造  [Not invited]
    高橋亮太, 鈴木博行, 杉浦美羽, Alain Boussac, 野口巧
    第48回日本植物生理学会年会  2007/03  愛媛大学
  • 炭酸水素イオンは酸素発生マンガンクラスターの配位子か?:赤外分光法による解析  [Not invited]
    青山智佳, 鈴木博行, 杉浦美羽, 野口巧
    第48回日本植物生理学会年会  2007/03  愛媛大学
  • Thermosynechococcus elongatus光化学系IIにおけるP680 リガンドの酸化還元電位への影響  [Not invited]
    杉浦美羽, Alain Boussac, 野口巧, Fabrice Rappaport
    第48回日本植物生理学会年会  2007/03  愛媛大学
  • 光化学系IIにおける酸素発生の分子機能と構造:部位特異的変異を導入した好熱性シアノバクテリアが解明のブレークスルーになる  [Invited]
    杉浦 美羽
    第87回 日本化学会春期年会 特別企画シンポジウム (光合成機能の分子メカニズムと工学応用 ~分子レベルの探求から太陽光エネルギー変換系への応用まで~)  2007/03  関西大学
  • Influence of the redox active Tyrosine D on the electron transfer in cyanobacterial Photosystem II  [Not invited]
    Malwina Szczepaniak, Miwa Sugiura, Alfred R. Holzwarth
    The 14th International Congress on Photosynthesis: Satellite Workshop on Photosynthetic Light-Harvesting Systems  2007
  • P680 ligand in the oxygen-evolving Photosystem II of Thermosynechococcus elongatus  [Not invited]
    Miwa Sugiura, Alain Boussac, Takumi Noguchi, Fabrice Rappaport
    The 14th International Congress on Photosynthesis: Satellite Workshop on Solar Energy and Artificial Photosynthesis  2007
  • Active Photosystem II Mutants from Thermosynechococcus elongatus  [Invited]
    Miwa Sugiura
    Seminar in Imperial College of London University (invited by Professor Dr. James Barber)  2006/11
  • Characterization of Active Photosystem II Mutants from Thermosynechococcus elongatus  [Invited]
    Miwa Sugiura
    Seminar in Max-Planck-Institut für Bionorhanische Chemie (Max-Planck-Institut für Kohlenforschumg Lembkestraße, Kleiner Hörsaal) (invited by Professor Dr. Alfred R. Holzwarth)  2006/11
  • Proton release pattern during photosynthetic water oxidation as studied by flash-induced FTIR difference spectroscopy  [Not invited]
    Hiroyuki Suzuki, Miwa Sugiura, Takumi Noguchi
    The 5th East Asian Biophysics Symposium  2006/11
  • Hydrogen bonding structure of the redox-active tyrosine YD in photosystem II as studied by FTIR spectroscopy and DFT calculations  [Not invited]
    Ryouta Takahashi, Hiroyuki Suzuki, Miwa Sugiura, Alain Boussac, Takumi Noguchi, Miwa Sugiura, Alain Boussac, Takumi Noguchi, Fabrice Rappaport
    The 5th East Asian Biophysics Symposium  2006/11
  • Effects of P680 ligand substitution in the oxygen-evolving Photosystem II of Thermosynechococcus elongatus  [Not invited]
    Miwa Sugiura, Alain Boussac, Takumi Noguchi, Fabrice Rappaport
    The 5th East Asian Biophysics Symposium  2006/11
  • FTIR study on the carboxylate ligands relevant to the calcium ion in the manganese cluster,  [Not invited]
    Hiroyuki Suzuki, Yuta Taguchi, Miwa Sugiura, Alain Boussac, Takumi Noguchi
    International Conference “Photosynthesis in the Post Genomic Era: Structure and Function of Photosystems”  2006/08
  • Characterization of active Photosystem II mutants from Thermosynechococcus elongatus  [Invited]
    Miwa Sugiura
    International Conference “Photosynthesis in the Post Genomic Era: Structure and Function of Photosystems”  2006/08  Pushchino, Moscow Region,  Russia
  • 光合成水分解反応におけるプロトン放出のFTIRによる検出  [Not invited]
    鈴木博行, 杉浦美羽, 野口巧
    光合成の色素系と反応中心に関するセミナー  2006/06  京都大学
  • Phenotype difference of tobacco plants expressing varied amounts of the nitrite transporter (CsNitr1-S)  [Not invited]
    Grant Griffith, Miwa Sugiura, Masaaki Takahashi
    第47回日本植物生理学会年会  2006/03  筑波大学
  • キュウリ亜硝酸トランスポーター・アイソフォーム(CsNitr1-S, CsNitr1-L)に特異的な機能  [Not invited]
    高橋正昭, Mihaela Georgescu, 杉浦美羽
    第47回日本植物生理学会年会  2006/03  筑波大学
  • 光合成酸素発生マンガンクラスターにおけるCa2+の構造的関与:ホウレンソウ及びシアノバクテリアのS状態サイクルおけるSr2+置換の効果  [Not invited]
    鈴木博行, 田口雄太, 杉浦美羽, Alain Boussac, 野口巧
    第47回日本植物生理学会年会  2006/03  筑波大学
  • Thermosynechococcus elongatusの光化学系IIにおけるTyrD周辺の水素結合ネットワーク  [Not invited]
    杉浦美羽, Alain Boussac, Sun Un
    第47回日本植物生理学会年会  2006/03  筑波大学
  • ATR法を用いた光化学系IIにおける電子伝達成分の赤外スペクトル測定  [Not invited]
    大久保辰則, 鈴木博行, 杉浦美羽, 野口巧
    第43回 日本生物物理学会2005年度年会  2005/11  札幌コンベンションセンター
  • 光化学系ⅡにおけるP680カチオンラジカルの電子状態  [Not invited]
    北嶋裕一, 水出光, 鞆達也, 杉浦美羽, 野口巧
    第43回 日本生物物理学会2005年度年会  2005/11  札幌コンベンションセンター
  • 酸素発生マンガンクラスターおけるCa2+の構造的関与:Sr2+置換によるFTIR解析  [Not invited]
    鈴木博行, 田口雄太, 杉浦美羽, Alain Boussac, 野口巧
    第43回 日本生物物理学会2005年度年会  2005/11  札幌コンベンションセンター
  • ATR-FTIR法による光化学系Ⅱ電子伝達成分の反応解析  [Not invited]
    大久保辰則, 杉浦美羽, 鈴木博行, 野口巧
    光合成の色素系と反応中心に関するセミナーXIII  2005/06  京都
  • 光化学系Ⅱにおけるβ-カロテン及びクロロフィルZの酸化メカニズム  [Not invited]
    北嶋裕一, 杉浦美羽, 野口巧
    光合成の色素系と反応中心に関するセミナーXIII  2005/06  京都
  • 振動分光法によるチロシン側鎖の水素結合構造の解析  [Not invited]
    高橋亮太, 鈴木博行, 杉浦美羽, 野口巧
    生体分子科学討論会  2005/06  神戸
  • FTIRによる光合成水分解反応におけるプロトン放出過程の解析  [Not invited]
    鈴木博行, 杉浦美羽, 野口巧
    生体分子科学討論会  2005/06  神戸
  • D2タンパク質に部位特異的変異を導入した好熱性ラン藻の光化学系II : TyrDの役割  [Not invited]
    杉浦美羽, Fabrice Rappaport, Klaus Brettel, 野口巧、A. William Rutherford, Alain Boussac
    第46回日本植物生理学会年会 (  2005/03  新潟
  • Site-directed mutagenesis on PSII in Thermosynechococcus elongatus  [Invited]
    Miwa Sugiura
    PHOTOSYNTHESIS and POST-GENOMIC ERA:"From Biophysics to Molecular Biology, a Path in the Research of Photosystem II" -Satelite meeting of in conjunction with the XIIIth International Congress on Photosynthesis  2004/08  Trois-Rivières, Québec, Canada
  • Site-directed Mutagensis in Photosystem II of the Thermophilic Cyanobacterium Thermosynechococcus elongatus  [Invited]
    Miwa Sugiura
    Seminar in ENEA Centro Casaccia (Invited by Professor Roberto Pilloton)  2004
  • Fourier transform infrared study on photosynthetic water oxidation using His-tagged PS II core complexes from Thermosynechococcus elongatus  [Not invited]
    Takumi Noguchi, Miwa Sugiura
    The 11th international Synposium on Phototrophi Prokaryotes  2003/08
  • Site-directed mutations in the thermophillic cyanobacterium Thermosynechococcus elongatus: Labelling and biochemical, EPR and FTIR analyses  [Not invited]
    Miwa Sugiura, Alain Boussac, Takumi Noguch, A. William Rutherford
    The 11th international Synposium on Phototrophi Prokaryotes  2003/08  Boston, USA
  • Site-directed mutations in the thermophilic cyanobacterium Thermosynechococcus elongatus : Labellings and biochemical, EPR and FTIR analyses  [Invited]
    Miwa Sugiura
    Photosynthèse membranaire : structures, fonctions, biogenèse et régulation  2003/06  Paris, France
  • Properties of highly-purified oxygen-evolving PSII core complexes from a thermophilic cyanobacteria T. elongatus having his-tagged CP43  [Not invited]
    Miwa Sugiura, Alain Boussac, A. William Rutherford
    EURESCO Conference: Molecular Bioenegetics of Cyanobacteria  2003/06
  • Site-directed Mutagenesis in the Thermophilic Cyanobacterium Thermosynechococcus elongatus  [Invited]
    Miwa Sugiura
    Seminar in Ruhr-Universitaet Bochum (invited by Professor Matthias Roegner)  2003
  • Etude du Complexe Mn4 du Photosystém II  [Not invited]
    Miwa Sugiura
    Seminaire in Université Paris-Sud  2003
  • Property and structure of His-tagged PSII core complexes from Thermosynechococcus elongatus  [Invited]
    Miwa Sugiura
    Biosensing Workshop  2002/06  ENEA Centro Casaccia, Rome, Italy
  • 赤外分光法による水分解系における水分子の反応の検出  [Not invited]
    野口巧, 杉浦美羽
    日本生物物理学会2002年度年会  2002/03  岡山大学
  • 赤外分光法による光合成酸素発生系におけるS状態反応サイクルの解析  [Not invited]
    野口巧, 杉浦美羽
    日本生物物理学会2001年度年会  2001/10  大阪大学
  • Localization of a new class of transporter for nitrogenous compound in chloroplast envelopes  [Invited]
    Miwa Sugiura, Masaaki Takahashi
    The 12th International Congress on Photosynthesis  2001/08  Brisbane, Australia
  • Investigation of the in vivo structure of the oxygen-evolving photosystem II (PS II) complex in Synechococcus elongatus  [Not invited]
    Miwa Sugiura, Masaaki Takahashi
    The 12th International Congress on Photosynthesis  2001/08
  • FTIRによる光合成水分解系における水分子の検出  [Not invited]
    野口巧, 杉浦美羽
    日本植物生理学会2001年度年会  2001/03  九州産業大学
  • 葉緑体の亜硝酸取り込みに関与するトランスポータの性質とcDNAの単離  [Not invited]
    杉浦美羽, 橘高隆一, 畑山裕亮, 高橋正昭
    日本植物生理学会2000年度年会  2000/03  椙山女学園大学
  • CP43 にヒスチジンタグを連結した好熱性ラン藻S. elongatus 光化学系 II コア複合体の性質  [Not invited]
    杉浦美羽, 井上頼直
    日本植物生理学会1999年度年会  1999/03  東北大学
  • Rapid isolation and characterization of His-tagged PS II core complex from Chlamydomonas  [Not invited]
    Miwa Sugiura, Yorinao Inoue, Jun Minagawa
    The 11th International Congress on Photosynthesis  1998/08
  • タバコ葉緑体におけるシトクロム P450 モノオキシゲナーゼと  [Not invited]
    杉浦美羽, 有馬大輔, 薮崎義康, 大川秀郎
    日本植物生理学会1997年度年会  1997/03  京都大学
  • ラット CYP1A1 およびその酵母 NADPH-P450 還元酵素との融合酵素のタバコ葉緑体への輸送と光合成電子伝達系との相互作用  [Not invited]
    杉浦美羽, 村中俊哉, 薮崎義康, 大川秀郎
    第68回 日本生化学会大会  1996/08  北海道
  • 葉緑体包膜に局在する亜硝酸トランスポーターの構造と形質転換植物を用いた機能の研究  [Not invited]
    岡桂子, 杉浦美羽, 尼子克己, 高橋正昭
    日本植物生理学会1996年度年会  1996/03  鹿児島大学
  • 植物の窒素トランスポーターに相同性を示す葉緑体包膜タンパク質のイオン輸送特性  [Not invited]
    高橋正昭, 杉浦美羽
    日本植物生理学会1996年度年会  1996/03  鹿児島大学
  • ラットCYP1A1およびラットCYP1A1-酵母NADPH-P450還元酵素融合酵素のタバコクロロプラストへの輸送と光化学系 I への影響  [Not invited]
    杉浦美羽, 村中俊哉, 薮崎義康, 大川秀郎
    日本植物生理学会1996年度年会  1996/03  鹿児島大学
  • cDNA Cloning and Expression in Escherichia coli and Saccharomyces cerevisiae of A Novel Tobacco Cytochrome P450 Induced by 2,4-D Treatment  [Not invited]
    Miwa Sugiura, Toshiyuki Sakaki, Yoshiyasu Yabusaki, Hideo Ohkawa
    3rd International Symposium on Cytochrome P450 Biodiversity  1995/10
  • タバコ培養細胞由来の新規シトクロムP450 cDNAの酵母での発現  [Not invited]
    杉浦美羽, 榊利之, 薮崎義康, 大川秀郎
    第67回 日本生化学会大会  1995/09  東北大学
  • タバコ培養細胞におけるシトクロムP450の一次構造と異種細胞での発現  [Invited]
    杉浦 美羽
    第67回 日本生化学会大会(コロキウム:微生物と植物のP450;生物機能性の分子機構)  1994/09
  • Two Types of Cytochrome P450 That Can Be Induced by 2,4-D in Tobacco Cultured Cells  [Not invited]
    Miwa Sugiura, Hiromasa Imaishi, Ohkawa Hideo
    2nd International Symposium on Cytochrome P450 of Microorganisms and Plants  1993/06
  • タバコ培養細胞の2,4-Dで誘導されるシトクロムP450分子種  [Not invited]
    杉浦美羽, 今石浩正, 大川秀郎
    第66回 日本生化学会大会  1993/03  東京大学教養学部
  • 葉緑体 Mn (II) 結合タンパク質の性質  [Not invited]
    高橋正昭, 杉浦美羽, 今井宣文, 橋本佳代子, 浅田浩二
    日本植物生理学会1992年度年会  1992/03

MISC

Awards & Honors

  • 2014/03 JST-さきがけ The Chemical Conversion of Light Energy Prize 2014
     Elucidation of Molecular Mechanisms of Highly Efficient Energy Conversion and Water Oxidation by Photosynthesis 
    受賞者: SUGIURA Miwa
  • 2013/09 2010年国際ソロプチミスト日本財団西日本リージョン松山 女性研究者「クラブ賞」
     光合成のエネルギー変換機能を改良した高効率な新規光合成太陽電池の開発 
    受賞者: 杉浦 美羽
  • 2011 日本女性科学者の会 奨励賞
     水の酸化を伴った光合成によるエネルギー変換機構と分子構造に関する研究 JPN

Research Grants & Projects

  • 光合成分子機構の学理解明と時空間制御による革新的光—物質変換系の創製
    文部科学省:科学研究費補助金(新学術領域研究 研究領域提案型)
    Date (from‐to) : 2017/04 -2022/03 
    Author : 沈 建仁, 杉浦 美羽
  • 光合成による水分解:プロトン共役電子移動の分子機作
    JSPS:科学研究費補助金(基盤B)
    Date (from‐to) : 2017/04 -2020/03 
    Author : 野口 巧, 杉浦 美羽
  • 光化学系IIの一次電子供与体P680の酸化還元電位の制御機構の解明
    JSPS:科学研究費補助金(基盤研究C)
    Date (from‐to) : 2017/04 -2020/03 
    Author : 杉浦 美羽
  • CO2の有効利用による食糧生産向上をめざした植物の光合成エネルギー変換機能の改良
    公益財団ひと・健康・未来研究財団:2016年度研究助成 環境分野<代表>
    Date (from‐to) : 2016/09 -2017/08 
    Author : 杉浦 美羽
  • 光従属栄養生育能を付与した好熱性シアノバクテリア作製による光合成研究基盤の構築
    JSPS:科学研究費補助金(挑戦的萌芽研究)
    Date (from‐to) : 2015 -2017 
    Author : 杉浦 美羽
  • 光合成による高効率エネルギー変換と水の酸化機構の解明
    日本科学技術振興財団(JST):さきがけ「光エネルギーと物質変換」
    Date (from‐to) : 2010 -2016 
    Author : 杉浦 美羽
  • 植物ナノバイオロジー研究の発展への貢献
    日本ナノメディシン交流協会:研究奨励寄付金
    Date (from‐to) : 2015 -2015 
    Author : 杉浦 美羽
  • 遺伝子改変PSIIタンパク質の水の酸化反応機構の解析
    日本科学技術振興財団(JST):戦略的創造研究推進事業国際強化支援
    Date (from‐to) : 2014 -2015 
    Author : 杉浦 美羽
  • 多量体形成する重金属結合蛋白質の分子構造に関する研究
    JSPS:科学研究費補助金(基盤研究C)
    Date (from‐to) : 2012 -2015 
    Author : 杉浦 美羽
  • 光従属栄養成長可能な新規好熱性ラン藻の作製による光合成研究基盤の構築
    愛媛大学:愛媛大学研究活性化事業・女性研究者支援(基盤研究)
    Date (from‐to) : 2012 -2013 
    Author : 杉浦 美羽
  • 光合成を利用したバイオテクノロジーによる水素生産技術の研究開発
    JSPS:科学研究費補助金(基盤研究C)<代表>
    Date (from‐to) : 2009 -2012 
    Author : 杉浦 美羽
  • The Mechanism of Water-Splitting in Photosynthesis
    Australian Research Council Discovery Projects <分担>:Australian Research Council Discovery Projects <分担>
    Date (from‐to) : 2007 -2012 
    Author : Thomas J. Wydrzynski(The Australian National University
  • 酸素発生型光合成微生物の遺伝子工学的改変による水素エネルギー生産技術の開発
    愛媛大学:研究開発支援経費(萌芽研究)<代表>
    Date (from‐to) : 2008 -2011 
    Author : 杉浦 美羽
  • 第15回 国際光合成会議(北京)
    日本学術振興会:国際学会等派遣事業 222033
    Date (from‐to) : 2010/08 -2010/08 
    Author : 杉浦 美羽
  • 光合成によるエネルギー変換機構の分子レベルでの解明と将来の展望 (Molecular Mechanism of Photosynthetic Energy Conversion: the Present Research and Future Prospects)
    分子科学国際研究会:岡崎国際コンファレンス開催費<代表>
    Date (from‐to) : 2010 -2010 
    Author : 杉浦 美羽
  • 光合成光化学系IIによるエネルギー変換の分子機構の解明と水素生産への応用
    日本学術振興会:二国間交流事業 :フランスCNRSとの共同研究
    Date (from‐to) : 2008 -2010 
    Author : 杉浦 美羽
  • 水素エネルギー生産を目指した光合成の水分解機構の解明と改良
    財団法人 日産科学振興財団:学術研究延長助成:環境研究部門<代表>
    Date (from‐to) : 2007 -2009 
    Author : 杉浦 美羽
  • Structural Studies of Photosystem II using mutant of Thermosynechococcus elongatus
    The Royal Society International Joint Project
    Date (from‐to) : 2007 -2009 
    Author : James Barber(Imperial College London・Department of Biochemistry, 授
  • 光化学系IIにおけるキノン電子受容体の反応と制御の分子メカニズム
    JSPS:科学研究費補助金(基盤研究C)<分担>
    Date (from‐to) : 2006 -2009 
    Author : 野口 巧, 数理物質科学研究科
  • 光合成の水分解機構の工学応用による水素生成の事業化に関する調査
    財団法人 新エネルギー・産業技術総合開発機構(NEDO):研究開発技術シーズ育成調査 <代表>
    Date (from‐to) : 2007/11 -2008/03 
    Author : 杉浦 美羽
  • 分子の視点から見る光合成(セミナー)
    自然科学研究機構:分子科学研究所共同利用研究セミナー開催<代表>
    Date (from‐to) : 2007 -2008 
    Author : 杉浦 美羽
  • 光独立栄養条件下で生育できる好熱性シアノバクテリアの作製と光合成研究への応用
    財団法人 長瀬科学技術振興財団:財団法人 長瀬科学技術振興財団:生化学部門
    Date (from‐to) : 2006 -2007 
    Author : 杉浦 美羽
  • 水素エネルギー生産を目指した光合成の水分解機構の解明と改良
    財団法人 日産科学振興財団:学術研究延長助成:環境研究部門<代表>
    Date (from‐to) : 2006 -2007 
    Author : 杉浦 美羽
  • 部位特異的変異を導入した光合成光化学系II反応中心の分子機構に関する研究
    日本学術振興会:二国間交流事業 :フランスCNRSとの共同研究
    Date (from‐to) : 2005 -2007 
    Author : 杉浦 美羽
  • ラン藻の部位特異的変異体の分光測定による光合成機構の解明
    JSPS:科学研究費補助金(基盤研究C-1)
    Date (from‐to) : 2002 -2004 
    Author : 野口 巧
  • Etude du Photosystème II de la cyanobactérie themophile Thermosynechococcus elongatus
    フランス国立科学研究省:若手共同研究者奨励金
    Date (from‐to) : 2002 -2003 
    Author : SUGIURA Miwa

愛媛大学教員活動実績

教育活動(B)

担当授業科目(B01)

  • 2019, the first semester, under graduate, 卒業研究Ⅰ
  • 2019, the first semester, master course, 化学ゼミナールⅠ
  • 2019, the first semester, master course, 化学ゼミナールⅢ
  • 2019, the first semester, master course, 分子科学課題演習I
  • 2019, the first semester, doctor course, 生命物質科学特論Ⅳ


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