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Structure of cyanobacterial photosystem I complexed with ferredoxin at 1.97 Å resolution. Commun Biol 2022; 5:951. [PMID: 36097054 PMCID: PMC9467995 DOI: 10.1038/s42003-022-03926-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 08/30/2022] [Indexed: 11/25/2022] Open
Abstract
Photosystem I (PSI) is a light driven electron pump transferring electrons from Cytochrome c6 (Cyt c6) to Ferredoxin (Fd). An understanding of this electron transfer process is hampered by a paucity of structural detail concerning PSI:Fd interface and the possible binding sites of Cyt c6. Here we describe the high resolution cryo-EM structure of Thermosynechococcus elongatus BP-1 PSI in complex with Fd and a loosely bound Cyt c6. Side chain interactions at the PSI:Fd interface including bridging water molecules are visualized in detail. The structure explains the properties of mutants of PsaE and PsaC that affect kinetics of Fd binding and suggests a molecular switch for the dissociation of Fd upon reduction. Calorimetry-based thermodynamic analyses confirms a single binding site for Fd and demonstrates that PSI:Fd complexation is purely driven by entropy. A possible reaction cycle for the efficient transfer of electrons from Cyt c6 to Fd via PSI is proposed. In order to aid the understanding of the electron transfer process within the cyanobacterial photosystem I, its structure - when complexed with Ferredoxin - is determined at 1.97 Å resolution.
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2
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Caspy I, Borovikova-Sheinker A, Klaiman D, Shkolnisky Y, Nelson N. The structure of a triple complex of plant photosystem I with ferredoxin and plastocyanin. NATURE PLANTS 2020. [PMID: 33020607 DOI: 10.1038/s41477-020-00779-779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The ability of photosynthetic organisms to use sunlight as a sole source of energy is endowed by two large membrane complexes-photosystem I (PSI) and photosystem II (PSII). PSI and PSII are the fundamental components of oxygenic photosynthesis, providing oxygen, food and an energy source for most living organisms on Earth. Currently, high-resolution crystal structures of these complexes from various organisms are available. The crystal structures of megadalton complexes have revealed excitation transfer and electron-transport pathways within the various complexes. PSI is defined as plastocyanin-ferredoxin oxidoreductase but a high-resolution structure of the entire triple supercomplex is not available. Here, using a new cryo-electron microscopy technique, we solve the structure of native plant PSI in complex with its electron donor plastocyanin and the electron acceptor ferredoxin. We reveal all of the contact sites and the modes of interaction between the interacting electron carriers and PSI.
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Affiliation(s)
- Ido Caspy
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Anna Borovikova-Sheinker
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Daniel Klaiman
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Yoel Shkolnisky
- School of Mathematical Sciences, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, Israel.
| | - Nathan Nelson
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
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3
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Caspy I, Borovikova-Sheinker A, Klaiman D, Shkolnisky Y, Nelson N. The structure of a triple complex of plant photosystem I with ferredoxin and plastocyanin. NATURE PLANTS 2020; 6:1300-1305. [PMID: 33020607 DOI: 10.1038/s41477-020-00779-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 09/03/2020] [Indexed: 06/11/2023]
Abstract
The ability of photosynthetic organisms to use sunlight as a sole source of energy is endowed by two large membrane complexes-photosystem I (PSI) and photosystem II (PSII). PSI and PSII are the fundamental components of oxygenic photosynthesis, providing oxygen, food and an energy source for most living organisms on Earth. Currently, high-resolution crystal structures of these complexes from various organisms are available. The crystal structures of megadalton complexes have revealed excitation transfer and electron-transport pathways within the various complexes. PSI is defined as plastocyanin-ferredoxin oxidoreductase but a high-resolution structure of the entire triple supercomplex is not available. Here, using a new cryo-electron microscopy technique, we solve the structure of native plant PSI in complex with its electron donor plastocyanin and the electron acceptor ferredoxin. We reveal all of the contact sites and the modes of interaction between the interacting electron carriers and PSI.
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Affiliation(s)
- Ido Caspy
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Anna Borovikova-Sheinker
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Daniel Klaiman
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Yoel Shkolnisky
- School of Mathematical Sciences, Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, Israel.
| | - Nathan Nelson
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
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4
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Schuller JM, Birrell JA, Tanaka H, Konuma T, Wulfhorst H, Cox N, Schuller SK, Thiemann J, Lubitz W, Sétif P, Ikegami T, Engel BD, Kurisu G, Nowaczyk MM. Structural adaptations of photosynthetic complex I enable ferredoxin-dependent electron transfer. Science 2018; 363:257-260. [PMID: 30573545 DOI: 10.1126/science.aau3613] [Citation(s) in RCA: 122] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 12/06/2018] [Indexed: 12/22/2022]
Abstract
Photosynthetic complex I enables cyclic electron flow around photosystem I, a regulatory mechanism for photosynthetic energy conversion. We report a 3.3-angstrom-resolution cryo-electron microscopy structure of photosynthetic complex I from the cyanobacterium Thermosynechococcus elongatus. The model reveals structural adaptations that facilitate binding and electron transfer from the photosynthetic electron carrier ferredoxin. By mimicking cyclic electron flow with isolated components in vitro, we demonstrate that ferredoxin directly mediates electron transfer between photosystem I and complex I, instead of using intermediates such as NADPH (the reduced form of nicotinamide adenine dinucleotide phosphate). A large rate constant for association of ferredoxin to complex I indicates efficient recognition, with the protein subunit NdhS being the key component in this process.
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Affiliation(s)
- Jan M Schuller
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
| | - James A Birrell
- Max Planck Institute for Chemical Energy Conversion, 45470 Mülheim an der Ruhr, Germany
| | - Hideaki Tanaka
- Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan.,Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
| | - Tsuyoshi Konuma
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Hannes Wulfhorst
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany.,Daiichi Sankyo Deutschland GmbH, Zielstattstr. 48, 81379 München, Germany
| | - Nicholas Cox
- Max Planck Institute for Chemical Energy Conversion, 45470 Mülheim an der Ruhr, Germany.,Research School of Chemistry, Australian National University, Canberra, ACT 2601, Australia
| | - Sandra K Schuller
- Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Jacqueline Thiemann
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion, 45470 Mülheim an der Ruhr, Germany
| | - Pierre Sétif
- Institut de Biologie Intégrative de la Cellule (I2BC), IBITECS, CEA, CNRS, Université Paris-Saclay, F-91198 Gif-sur-Yvette, France
| | - Takahisa Ikegami
- Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Benjamin D Engel
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Genji Kurisu
- Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan. .,Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
| | - Marc M Nowaczyk
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany.
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5
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Marco P, Kozuleva M, Eilenberg H, Mazor Y, Gimeson P, Kanygin A, Redding K, Weiner I, Yacoby I. Binding of ferredoxin to algal photosystem I involves a single binding site and is composed of two thermodynamically distinct events. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:234-243. [DOI: 10.1016/j.bbabio.2018.01.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 01/07/2018] [Accepted: 01/08/2018] [Indexed: 10/18/2022]
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6
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Kubota-Kawai H, Mutoh R, Shinmura K, Sétif P, Nowaczyk MM, Rögner M, Ikegami T, Tanaka H, Kurisu G. X-ray structure of an asymmetrical trimeric ferredoxin-photosystem I complex. NATURE PLANTS 2018; 4:218-224. [PMID: 29610537 DOI: 10.1038/s41477-018-0130-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 03/06/2018] [Indexed: 05/03/2023]
Abstract
Photosystem I (PSI), a large protein complex located in the thylakoid membrane, mediates the final step in light-driven electron transfer to the stromal electron carrier protein ferredoxin (Fd). Here, we report the first structural description of the PSI-Fd complex from Thermosynechococcus elongatus. The trimeric PSI complex binds three Fds in a non-equivalent manner. While each is recognized by a PSI protomer in a similar orientation, the distances between Fds and the PSI redox centres differ. Fd binding thus entails loss of the exact three-fold symmetry of the PSI's soluble subunits, inducing structural perturbations which are transferred to the lumen through PsaF. Affinity chromatography and nuclear magnetic resonance analyses of PSI-Fd complexes support the existence of two different Fd-binding states, with one Fd being more tightly bound than the others. We propose a dynamic structural basis for productive complex formation, which supports fast electron transfer between PSI and Fd.
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Affiliation(s)
- Hisako Kubota-Kawai
- Institute for Protein Research, Osaka University, Osaka, Japan
- National Institute for Basic Biology, Aichi, Japan
| | - Risa Mutoh
- Institute for Protein Research, Osaka University, Osaka, Japan
- Department of Applied Physics, Faculty of Science, Fukuoka University, Fukuoka, Japan
| | - Kanako Shinmura
- Institute for Protein Research, Osaka University, Osaka, Japan
| | - Pierre Sétif
- Institut de Biologie Intégrative de la Cellule (I2BC), IBITECS, CEA, CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Marc M Nowaczyk
- Plant Biochemistry, Faculty of Biology & Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Matthias Rögner
- Plant Biochemistry, Faculty of Biology & Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Takahisa Ikegami
- Graduate School of Medical Life Science, Yokohama City University, Yokohama, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama, Japan
| | - Hideaki Tanaka
- Institute for Protein Research, Osaka University, Osaka, Japan
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama, Japan
- Department of Macromolecular Science, Graduate School of Science, Osaka, Japan
| | - Genji Kurisu
- Institute for Protein Research, Osaka University, Osaka, Japan.
- Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Saitama, Japan.
- Department of Macromolecular Science, Graduate School of Science, Osaka, Japan.
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7
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Mignée C, Mutoh R, Krieger-Liszkay A, Kurisu G, Sétif P. Gallium ferredoxin as a tool to study the effects of ferredoxin binding to photosystem I without ferredoxin reduction. PHOTOSYNTHESIS RESEARCH 2017; 134:251-263. [PMID: 28205062 DOI: 10.1007/s11120-016-0332-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 12/27/2016] [Indexed: 06/06/2023]
Abstract
Reduction of ferredoxin by photosystem I (PSI) involves the [4Fe-4S] clusters FA and FB harbored by PsaC, with FB being the direct electron transfer partner of ferredoxin (Fd). Binding of the redox-inactive gallium ferredoxin to PSI was investigated by flash-absorption spectroscopy, studying both the P700+ decay and the reduction of the native iron Fd in the presence of FdGa. FdGa binding resulted in a faster recombination between P700+ and (FA, FB)-, a slower electron escape from (FA, FB)- to exogenous acceptors, and a decreased amount of intracomplex FdFe reduction, in accordance with competitive binding between FdFe and FdGa. [FdGa] titrations of these effects revealed that the dissociation constant for the PSI:FdGa complex is different whether (FA, FB) is oxidized or singly reduced. This difference in binding, together with the increase in the recombination rate, could both be attributed to a c. -30 mV shift of the midpoint potential of (FA, FB), considered as a single electron acceptor, due to FdGa binding. This effect of FdGa binding, which can be extrapolated to FdFe because of the highly similar structure and the identical charge of the two Fds, should help irreversibility of electron transfer within the PSI:Fd complex. The effect of Fd binding on the individual midpoint potentials of FA and FB is also discussed with respect to the possible consequences on intra-PSI electron transfer and on the escape process.
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Affiliation(s)
- Clara Mignée
- Institut de Biologie Intégrative de la Cellule (I2BC), IBITECS, CEA, CNRS, Univ. Paris-Saclay, F-91198, Gif-sur-Yvette cedex, France
| | - Risa Mutoh
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Anja Krieger-Liszkay
- Institut de Biologie Intégrative de la Cellule (I2BC), IBITECS, CEA, CNRS, Univ. Paris-Saclay, F-91198, Gif-sur-Yvette cedex, France
| | - Genji Kurisu
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Pierre Sétif
- Institut de Biologie Intégrative de la Cellule (I2BC), IBITECS, CEA, CNRS, Univ. Paris-Saclay, F-91198, Gif-sur-Yvette cedex, France.
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8
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Sétif P, Mutoh R, Kurisu G. Dynamics and energetics of cyanobacterial photosystem I:ferredoxin complexes in different redox states. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2017; 1858:483-496. [DOI: 10.1016/j.bbabio.2017.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/24/2017] [Accepted: 04/12/2017] [Indexed: 10/19/2022]
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9
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Shikanai T. Chloroplast NDH: A different enzyme with a structure similar to that of respiratory NADH dehydrogenase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:1015-22. [DOI: 10.1016/j.bbabio.2015.10.013] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 10/21/2015] [Accepted: 10/26/2015] [Indexed: 11/28/2022]
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10
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Veit S, Nagadoi A, Rögner M, Rexroth S, Stoll R, Ikegami T. The cyanobacterial cytochrome b6f subunit PetP adopts an SH3 fold in solution. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:705-14. [DOI: 10.1016/j.bbabio.2016.03.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 03/02/2016] [Accepted: 03/23/2016] [Indexed: 12/22/2022]
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11
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Quaranta A, Lagoutte B, Frey J, Sétif P. Photoreduction of the ferredoxin/ferredoxin-NADP(+)-reductase complex by a linked ruthenium polypyridyl chromophore. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2016; 160:347-54. [PMID: 27180037 DOI: 10.1016/j.jphotobiol.2016.04.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 04/26/2016] [Accepted: 04/28/2016] [Indexed: 11/18/2022]
Abstract
Photosynthetic ferredoxin and its main partner ferredoxin-NADP(+)-reductase (FNR) are key proteins during the photoproduction of reductive power involved in photosynthetic growth. In this work, we used covalent attachment of ruthenium derivatives to different cysteine mutants of ferredoxin to trigger by laser-flash excitation both ferredoxin reduction and subsequent electron transfer from reduced ferredoxin to FNR. Rates and yields of reduction of the ferredoxin [2Fe-2S] cluster by reductively quenched Ru* could be measured for the first time for such a low redox potential protein whereas ferredoxin-FNR electron transfer was characterized in detail for one particular Ru-ferredoxin covalent adduct. For this adduct, the efficiency of FNR single reduction by reduced ferredoxin was close to 100% under both first-order and diffusion-limited second-order conditions. Interprotein intracomplex electron transfer was measured unambiguously for the first time with a fast rate of c. 6500s(-1). Our measurements point out that Ru photosensitizing is a powerful approach to study the functional interactions of ferredoxin with its numerous partners besides FNR.
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Affiliation(s)
- Annamaria Quaranta
- CEA, iBiTec-S/SB2SM, CEA Saclay, 91191 Gif sur Yvette, France; Université Paris-Saclay, I2BC, UMR 9198, 91190 Gif sur Yvette, France
| | | | - Julien Frey
- CEA, iBiTec-S/SB2SM, CEA Saclay, 91191 Gif sur Yvette, France
| | - Pierre Sétif
- CEA, iBiTec-S/SB2SM, CEA Saclay, 91191 Gif sur Yvette, France; Université Paris-Saclay, I2BC, UMR 9198, 91190 Gif sur Yvette, France.
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12
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Cashman DJ, Zhu T, Simmerman RF, Scott C, Bruce BD, Baudry J. Molecular interactions between photosystem I and ferredoxin: an integrated energy frustration and experimental model. J Mol Recognit 2015; 27:597-608. [PMID: 25178855 DOI: 10.1002/jmr.2384] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Revised: 03/21/2014] [Accepted: 04/18/2014] [Indexed: 11/10/2022]
Abstract
The stromal domain (PsaC, PsaD, and PsaE) of photosystem I (PSI) reduces transiently bound ferredoxin (Fd) or flavodoxin. Experimental structures exist for all of these protein partners individually, but no experimental structure of the PSI/Fd or PSI/flavodoxin complexes is presently available. Molecular models of Fd docked onto the stromal domain of the cyanobacterial PSI site are constructed here utilizing X-ray and NMR structures of PSI and Fd, respectively. Predictions of potential protein-protein interaction regions are based on experimental site-directed mutagenesis and cross-linking studies to guide rigid body docking calculations of Fd into PSI, complemented by energy landscape theory to bring together regions of high energetic frustration on each of the interacting proteins. The results identify two regions of high localized frustration on the surface of Fd that contain negatively charged Asp and Glu residues. This study predicts that these regions interact predominantly with regions of high localized frustration on the PsaC, PsaD, and PsaE chains of PSI, which include several residues predicted by previous experimental studies.
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Affiliation(s)
- Derek J Cashman
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, 37996, USA; UT/ORNL Center for Molecular Biophysics, Oak Ridge National Laboratory, University of Tennessee, Oak Ridge, TN, 37831, USA
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13
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Electron-transfer kinetics in cyanobacterial cells: methyl viologen is a poor inhibitor of linear electron flow. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1847:212-222. [PMID: 25448535 DOI: 10.1016/j.bbabio.2014.10.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 10/24/2014] [Accepted: 10/28/2014] [Indexed: 01/13/2023]
Abstract
The inhibitor methyl viologen (MV) has been widely used in photosynthesis to study oxidative stress. Its effects on electron transfer kinetics in Synechocystis sp. PCC6803 cells were studied to characterize its electron-accepting properties. For the first hundreds of flashes following MV addition at submillimolar concentrations, the kinetics of NADPH formation were hardly modified (less than 15% decrease in signal amplitude) with a significant signal decrease only observed after more flashes or continuous illumination. The dependence of the P700 photooxidation kinetics on the MV concentration exhibited a saturation effect at 0.3 mM MV, a concentration which inhibits the recombination reactions in photosystem I. The kinetics of NADPH formation and decay under continuous light with MV at 0.3 mM showed that MV induces the oxidation of the NADP pool in darkness and that the yield of linear electron transfer decreased by only 50% after 1.5-2 photosystem-I turnovers. The unexpectedly poor efficiency of MV in inhibiting NADPH formation was corroborated by in vitro flash-induced absorption experiments with purified photosystem-I, ferredoxin and ferredoxin-NADP(+)-oxidoreductase. These experiments showed that the second-order rate constants of MV reduction are 20 to 40-fold smaller than the competing rate constants involved in reduction of ferredoxin and ferredoxin-NADP(+)-oxidoreductase. The present study shows that MV, which accepts electrons in vivo both at the level of photosystem-I and ferredoxin, can be used at submillimolar concentrations to inhibit recombination reactions in photosystem-I with only a moderate decrease in the efficiency of fast reactions involved in linear electron transfer and possibly cyclic electron transfer.
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14
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Srivastava AP, Knaff DB, Sétif P. Kinetic Studies of a Ferredoxin-Dependent Cyanobacterial Nitrate Reductase. Biochemistry 2014; 53:5092-101. [DOI: 10.1021/bi500386n] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Anurag P. Srivastava
- Department
of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
| | - David B. Knaff
- Department
of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
- Center
for Biotechnology and Genomics, Texas Tech University, Lubbock, Texas 79409-3132, United States
| | - Pierre Sétif
- iBiTec-S, CNRS UMR 8221,
CEA Saclay, 91191 Gif-sur-Yvette, France
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15
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Yamamoto H, Shikanai T. In planta mutagenesis of Src homology 3 domain-like fold of NdhS, a ferredoxin-binding subunit of the chloroplast NADH dehydrogenase-like complex in Arabidopsis: a conserved Arg-193 plays a critical role in ferredoxin binding. J Biol Chem 2013; 288:36328-37. [PMID: 24225949 DOI: 10.1074/jbc.m113.511584] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Chloroplast NADH dehydrogenase-like (NDH) complex mediates cyclic electron transport around photosystem I and chlororespiration in angiosperms. The Src homology 3 domain (SH3)-like fold protein NdhS/CRR31 is an NDH subunit that is necessary for high affinity binding of ferredoxin, indicating that chloroplast NDH functions as a ferredoxin:plastoquinone oxidoreductase. However, the mechanism of the interaction between NdhS and ferredoxin is unclear. In this study, we analyzed their interaction in planta by using site-directed mutagenesis of NdhS. In general, binding of ferredoxin to its target proteins depends on electrostatic interaction. In silico analysis predicted the presence of a positively charged pocket in the SH3-like domain of NdhS, where nine charged residues are highly conserved among plants. Systematic alteration of these sites with neutral glutamine revealed that only arginine 193 was required for high NDH activity in vivo. Further replacement of arginine 193 with negatively charged aspartate or glutamate or hydrophobic alanine significantly decreased the efficiency of ferredoxin-dependent plastoquinone reduction by NDH in ruptured chloroplasts. Similar results were obtained in in vivo analyses of NDH activity and electron transport. From these results, we propose that the positive charge of arginine 193 in the SH3-like domain of NdhS is critical for electrostatic interaction with ferredoxin in vivo.
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Affiliation(s)
- Hiroshi Yamamoto
- From the Department of Botany, Graduate School of Science, Kyoto University, Kyoto 606-8502 and
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16
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Wittenberg G, Sheffler W, Darchi D, Baker D, Noy D. Accelerated electron transport from photosystem I to redox partners by covalently linked ferredoxin. Phys Chem Chem Phys 2013; 15:19608-14. [PMID: 24129892 DOI: 10.1039/c3cp53264j] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photosystem I is a highly efficient and potent light-induced reductase that is considered to be an appealing target for integration into hybrid solar fuel production systems. However, rapid transport of multiple electrons from the reducing end of photosystem I to downstream processes in vivo is limited by the diffusion of its native redox partner ferredoxin that is a single electron carrier. Here, we describe the design and construction of a faster electron transfer interface based on anchoring ferredoxin to the reducing end of photosystem I thereby confining the diffusion space of ferredoxin to the near vicinity of its photosystem I binding and reduction site. This was achieved by fusing ferredoxin to the PsaE subunit of photosystem I by a flexible peptide linker and reconstituting PSI in vitro with the new fusion protein. A computational algorithm was developed in order to determine the optimal linker length that will confine ferredoxin to the vicinity of photosystem I's reducing end without restricting the formation of electron transfer complexes. According to the calculation, we reconstituted photosystem I with three fusion proteins comprising PsaE and ferredoxin separated by linkers of different lengths, namely 14, 19, and 25 amino acids, and tested their effect on electron transfer rates from photosystem I to downstream processes. Indeed, we found a significant enhancement of light dependent NADPH synthesis using photosystems containing the PsaE-ferredoxin fusion proteins, equivalent to a ten-fold increase in soluble ferredoxin concentration. We propose that such a system could be used for other ferredoxin dependent redox reactions, such as the enzymatic production of hydrogen, a promising alternative fuel. As the system is comprised entirely of natural amino acids and biological cofactors, it could be integrated into the energy conversion apparatus of photosynthetic organisms by genetic engineering.
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Affiliation(s)
- Gal Wittenberg
- Plant Sciences Department, Weizmann Institute of Science, Rehovot 7610001, Israel
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17
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Srivastava AP, Hirasawa M, Bhalla M, Chung JS, Allen JP, Johnson MK, Tripathy JN, Rubio LM, Vaccaro B, Subramanian S, Flores E, Zabet-Moghaddam M, Stitle K, Knaff DB. Roles of four conserved basic amino acids in a ferredoxin-dependent cyanobacterial nitrate reductase. Biochemistry 2013; 52:4343-53. [PMID: 23692082 DOI: 10.1021/bi400354n] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The roles of four conserved basic amino acids in the reaction catalyzed by the ferredoxin-dependent nitrate reductase from the cyanobacterium Synechococcus sp. PCC 7942 have been investigated using site-directed mutagenesis in combination with measurements of steady-state kinetics, substrate-binding affinities, and spectroscopic properties of the enzyme's two prosthetic groups. Replacement of either Lys58 or Arg70 by glutamine leads to a complete loss of activity, both with the physiological electron donor, reduced ferredoxin, and with a nonphysiological electron donor, reduced methyl viologen. More conservative, charge-maintaining K58R and R70K variants were also completely inactive. Replacement of Lys130 by glutamine produced a variant that retained 26% of the wild-type activity with methyl viologen as the electron donor and 22% of the wild-type activity with ferredoxin as the electron donor, while replacement by arginine produces a variant that retains a significantly higher percentage of the wild-type activity with both electron donors. In contrast, replacement of Arg146 by glutamine had minimal effect on the activity of the enzyme. These results, along with substrate-binding and spectroscopic measurements, are discussed in terms of an in silico structural model for the enzyme.
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Affiliation(s)
- Anurag P Srivastava
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
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18
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Moal G, Lagoutte B. Photo-induced electron transfer from photosystem I to NADP(+): characterization and tentative simulation of the in vivo environment. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1817:1635-45. [PMID: 22683536 DOI: 10.1016/j.bbabio.2012.05.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Revised: 05/28/2012] [Accepted: 05/30/2012] [Indexed: 12/01/2022]
Abstract
The photoproduction of NADPH in photosynthetic organisms requires the successive or concomitant interaction of at least three proteins: photosystem I (PSI), ferredoxin (Fd) and ferredoxin:NADP(+) oxidoreductase (FNR). These proteins and their surrounding medium have been carefully analysed in the cyanobacterium Synechocystis sp. PCC 6803. A high value of 550mg/ml was determined for the overall solute content of the cell soluble compartment. PSI and Fd are present at similar concentrations, around 500μM, whereas the FNR associated to phycobilisome is about 4 fold less concentrated. Membrane densities of FNR and trimeric PSI have been estimated to 2000 and 2550 per μm(2), respectively. An artificial confinement of Fd to PSI was designed using fused constructs between Fd and PsaE, a peripheral and stroma located PSI subunit. The best covalent system in terms of photocatalysed NADPH synthesis can be equivalent to the free system in a dilute medium. In a macrosolute crowded medium (375mg/ml), this optimized PSI/Fd covalent complex exhibited a huge superiority compared to the free system. This is a likely consequence of restrained diffusion constraints due to the vicinity of two out of the three protein partners. In vivo, Fd is the free partner, but the constant proximity between PSI and the phycobilisome associated FNR creates a similar situation, with two closely associated partners. This organization seems well adapted for an efficient in vivo production of the stable and fast diffusing NADPH.
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Affiliation(s)
- Gwenaëlle Moal
- Service de Bioenergetique, Biologie Structurale et Mecanismes, Gif sur Yvette, France
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19
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Winkler M, Kawelke S, Happe T. Light driven hydrogen production in protein based semi-artificial systems. BIORESOURCE TECHNOLOGY 2011; 102:8493-8500. [PMID: 21696949 DOI: 10.1016/j.biortech.2011.05.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2010] [Revised: 05/04/2011] [Accepted: 05/08/2011] [Indexed: 05/31/2023]
Abstract
Photobiological hydrogen production has recently attracted interest in terms of being a potential source for an alternative energy carrier. Especially the natural light driven hydrogen metabolism of unicellular green algae appears as an attractive blueprint for a clean and potentially unlimited dihydrogen source. However, the efficiency of in vivo systems is limited by physiological and evolutionary constraints and scientists only begin to understand the regulatory networks influencing cellular hydrogen production. A growing number of projects aim at circumventing these limitations by focusing on semi-artificial systems. They reconstitute parts of the native electron transfer chains in vitro, combining photosystem I as a photoactive element with a proton reducing catalytic element such as hydrogenase enzymes or noble metal nanoparticles. This review summarizes various approaches and discusses limitations that have to be overcome in order to establish economically applicable systems.
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Affiliation(s)
- Martin Winkler
- Ruhr-Universität Bochum, Fakultät für Biologie und Biotechnologie, Lehrstuhl für Biochemie der Pflanzen, AG Photobiotechnologie, 44780 Bochum, Germany
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20
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Yamamoto H, Peng L, Fukao Y, Shikanai T. An Src homology 3 domain-like fold protein forms a ferredoxin binding site for the chloroplast NADH dehydrogenase-like complex in Arabidopsis. THE PLANT CELL 2011; 23:1480-93. [PMID: 21505067 PMCID: PMC3101538 DOI: 10.1105/tpc.110.080291] [Citation(s) in RCA: 167] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 03/07/2011] [Accepted: 04/05/2011] [Indexed: 05/18/2023]
Abstract
Some subunits of chloroplast NAD(P)H dehydrogenase (NDH) are related to those of the respiratory complex I, and NDH mediates photosystem I (PSI) cyclic electron flow. Despite extensive surveys, the electron donor and its binding subunits have not been identified. Here, we identified three novel components required for NDH activity. CRRJ and CRRL are J- and J-like proteins, respectively, and are components of NDH subcomplex A. CRR31 is an Src homology 3 domain-like fold protein, and its C-terminal region may form a tertiary structure similar to that of PsaE, a ferredoxin (Fd) binding subunit of PSI, although the sequences are not conserved between CRR31 and PsaE. Although CRR31 can accumulate in thylakoids independently of NDH, its accumulation requires CRRJ, and CRRL accumulation depends on CRRJ and NDH. CRR31 was essential for the efficient operation of Fd-dependent plastoquinone reduction in vitro. The phenotype of crr31 pgr5 suggested that CRR31 is required for NDH activity in vivo. We propose that NDH functions as a PGR5-PGRL1 complex-independent Fd:plastoquinone oxidoreductase in chloroplasts and rename it the NADH dehydrogenase-like complex.
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Affiliation(s)
- Hiroshi Yamamoto
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Lianwei Peng
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Yoichiro Fukao
- Plant Global Educational Project, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma 630-0101, Japan
| | - Toshiharu Shikanai
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
- Address correspondence to
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21
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Busch A, Hippler M. The structure and function of eukaryotic photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1807:864-77. [PMID: 20920463 DOI: 10.1016/j.bbabio.2010.09.009] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Revised: 09/20/2010] [Accepted: 09/28/2010] [Indexed: 12/27/2022]
Abstract
Eukaryotic photosystem I consists of two functional moieties: the photosystem I core, harboring the components for the light-driven charge separation and the subsequent electron transfer, and the peripheral light-harvesting complex (LHCI). While the photosystem I-core remained highly conserved throughout the evolution, with the exception of the oxidizing side of photosystem I, the LHCI complex shows a high degree of variability in size, subunits composition and bound pigments, which is due to the large variety of different habitats photosynthetic organisms dwell in. Besides summarizing the most current knowledge on the photosystem I-core structure, we will discuss the composition and structure of the LHCI complex from different eukaryotic organisms, both from the red and the green clade. Furthermore, mechanistic insights into electron transfer between the donor and acceptor side of photosystem I and its soluble electron transfer carrier proteins will be given. This article is part of a Special Issue entitled: Regulation of Electron Transport in Chloroplasts.
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Affiliation(s)
- Andreas Busch
- Department of Plant Biology and Biotechnology, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
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22
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Sétif P, Harris N, Lagoutte B, Dotson S, Weinberger SR. Detection of the Photosystem I:Ferredoxin Complex by Backscattering Interferometry. J Am Chem Soc 2010; 132:10620-2. [DOI: 10.1021/ja102208u] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pierre Sétif
- iBiTec-S, URA CNRS 2096, CEA Saclay, 91191 Gif sur Yvette, France and Molecular Sensing Inc. (MSI), Montara, California 94037
| | - Nathan Harris
- iBiTec-S, URA CNRS 2096, CEA Saclay, 91191 Gif sur Yvette, France and Molecular Sensing Inc. (MSI), Montara, California 94037
| | - Bernard Lagoutte
- iBiTec-S, URA CNRS 2096, CEA Saclay, 91191 Gif sur Yvette, France and Molecular Sensing Inc. (MSI), Montara, California 94037
| | - Stephen Dotson
- iBiTec-S, URA CNRS 2096, CEA Saclay, 91191 Gif sur Yvette, France and Molecular Sensing Inc. (MSI), Montara, California 94037
| | - Scot. R Weinberger
- iBiTec-S, URA CNRS 2096, CEA Saclay, 91191 Gif sur Yvette, France and Molecular Sensing Inc. (MSI), Montara, California 94037
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23
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Korn A, Ajlani G, Lagoutte B, Gall A, Sétif P. Ferredoxin:NADP+ oxidoreductase association with phycocyanin modulates its properties. J Biol Chem 2009; 284:31789-97. [PMID: 19759024 DOI: 10.1074/jbc.m109.024638] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In photosynthetic organisms, ferredoxin:NADP(+) oxidoreductase (FNR) is known to provide NADPH for CO(2) assimilation, but it also utilizes NADPH to provide reduced ferredoxin. The cyanobacterium Synechocystis sp. strain PCC6803 produces two FNR isoforms, a small one (FNR(S)) similar to the one found in plant plastids and a large one (FNR(L)) that is associated with the phycobilisome, a light-harvesting complex. Here we show that a mutant lacking FNR(L) exhibits a higher NADP(+)/NADPH ratio. We also purified to homogeneity a phycobilisome subcomplex comprising FNR(L,) named FNR(L)-PC. The enzymatic activities of FNR(L)-PC were compared with those of FNR(S). During NADPH oxidation, FNR(L)-PC exhibits a 30% decrease in the Michaelis constant K(m)((NADPH)), and a 70% increase in K(m)((ferredoxin)), which is in agreement with its predicted lower activity of ferredoxin reduction. During NADP(+) reduction, the FNR(L)-PC shows a 29/43% decrease in the rate of single electron transfer from reduced ferredoxin in the presence/absence of NADP(+). The increase in K(m)((ferredoxin)) and the rate decrease of single reduction are attributed to steric hindrance by the phycocyanin moiety of FNR(L)-PC. Both isoforms are capable of catalyzing the NADP(+) reduction under multiple turnover conditions. Furthermore, we obtained evidence that, under high ionic strength conditions, electron transfer from reduced ferredoxin is rate limiting during this process. The differences that we observe might not fully explain the in vivo properties of the Synechocystis mutants expressing only one of the isoforms. Therefore, we advocate that FNR localization and/or substrates availability are essential in vivo.
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Affiliation(s)
- Anja Korn
- Institut de Biologie et de Technologie de Saclay, Commissariat à L'Energie Atomique, CNRS, F-91191 Gif sur Yvette, France
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24
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Sétif P, Hirasawa M, Cassan N, Lagoutte B, Tripathy JN, Knaff DB. New Insights into the Catalytic Cycle of Plant Nitrite Reductase. Electron Transfer Kinetics and Charge Storage. Biochemistry 2009; 48:2828-38. [DOI: 10.1021/bi802096f] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Pierre Sétif
- CEA, iBiTecS, F-91191 Gif sur Yvette, France, CNRS, URA 2096, F-91191 Gif sur Yvette, France, and Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
| | - Masakazu Hirasawa
- CEA, iBiTecS, F-91191 Gif sur Yvette, France, CNRS, URA 2096, F-91191 Gif sur Yvette, France, and Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
| | - Nicolas Cassan
- CEA, iBiTecS, F-91191 Gif sur Yvette, France, CNRS, URA 2096, F-91191 Gif sur Yvette, France, and Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
| | - Bernard Lagoutte
- CEA, iBiTecS, F-91191 Gif sur Yvette, France, CNRS, URA 2096, F-91191 Gif sur Yvette, France, and Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
| | - Jatindra N. Tripathy
- CEA, iBiTecS, F-91191 Gif sur Yvette, France, CNRS, URA 2096, F-91191 Gif sur Yvette, France, and Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
| | - David B. Knaff
- CEA, iBiTecS, F-91191 Gif sur Yvette, France, CNRS, URA 2096, F-91191 Gif sur Yvette, France, and Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
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25
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Goñi G, Herguedas B, Hervás M, Peregrina JR, De la Rosa MA, Gómez-Moreno C, Navarro JA, Hermoso JA, Martínez-Júlvez M, Medina M. Flavodoxin: a compromise between efficiency and versatility in the electron transfer from Photosystem I to Ferredoxin-NADP(+) reductase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2008; 1787:144-54. [PMID: 19150326 DOI: 10.1016/j.bbabio.2008.12.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2008] [Revised: 12/01/2008] [Accepted: 12/09/2008] [Indexed: 11/18/2022]
Abstract
Under iron-deficient conditions Flavodoxin (Fld) replaces Ferredoxin in Anabaena as electron carrier from Photosystem I (PSI) to Ferredoxin-NADP(+) reductase (FNR). Several residues modulate the Fld interaction with FNR and PSI, but no one appears as specifically critical for efficient electron transfer (ET). Fld shows a strong dipole moment, with its negative end directed towards the flavin ring. The role of this dipole moment in the processes of interaction and ET with positively charged surfaces exhibited by PSI and FNR has been analysed by introducing single and multiple charge reversal mutations on the Fld surface. Our data confirm that in this system interactions do not rely on a precise complementary surface of the reacting molecules. In fact, they indicate that the initial orientation driven by the alignment of dipole moment of the Fld molecule with that of the partner contributes to the formation of a bunch of alternative binding modes competent for the efficient ET reaction. Additionally, the fact that Fld uses different interaction surfaces to dock to PSI and to FNR is confirmed.
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Affiliation(s)
- Guillermina Goñi
- Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, 50009-Zaragoza, Spain
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26
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Gitlin I, Carbeck JD, Whitesides GM. Why are proteins charged? Networks of charge-charge interactions in proteins measured by charge ladders and capillary electrophoresis. Angew Chem Int Ed Engl 2007; 45:3022-60. [PMID: 16619322 DOI: 10.1002/anie.200502530] [Citation(s) in RCA: 196] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Almost all proteins contain charged amino acids. While the function in catalysis or binding of individual charges in the active site can often be identified, it is less clear how to assign function to charges beyond this region. Are they necessary for solubility? For reasons other than solubility? Can manipulating these charges change the properties of proteins? A combination of capillary electrophoresis (CE) and protein charge ladders makes it possible to study the roles of charged residues on the surface of proteins outside the active site. This method involves chemical modification of those residues to generate a large number of derivatives of the protein that differ in charge. CE separates those derivatives into groups with the same number of modified charged groups. By studying the influence of charge on the properties of proteins using charge ladders, it is possible to estimate the net charge and hydrodynamic radius and to infer the role of charged residues in ligand binding and protein folding.
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Affiliation(s)
- Irina Gitlin
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, MA 02138, USA
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27
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Ihara M, Nakamoto H, Kamachi T, Okura I, Maeda M. Photoinduced hydrogen production by direct electron transfer from photosystem I cross-linked with cytochrome c3 to [NiFe]-hydrogenase. Photochem Photobiol 2007; 82:1677-85. [PMID: 16836469 DOI: 10.1562/2006-05-07-ra-893] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The photosynthetic reaction center is an efficient molecular device for the conversion of light energy to chemical energy. In a previous study, we synthesized the hydrogenase/photosystem I (PSI) complex, in which Ralstonia hydrogenase was linked to the cytoplasmic side of Synechocystis PSI, to modify PSI so that it photoproduced molecular hydrogen (H2). In that study, hydrogenase was fused with a PSI subunit, PsaE, and the resulting hydrogenase-PsaE fusion protein was self-assembled with PsaE-free PSI to give the hydrogenase/PSI complex. Although the hydrogenase/PSI complex served as a direct light-to-H2 conversion system in vitro, the activity was totally suppressed by adding physiological PSI partners, ferredoxin (Fd) and ferredoxin-NADP+-reductase (FNR). In the present study, to establish an H2 photoproduction system in which the activity is not interrupted by Fd and FNR, position 40 of PsaE from Synechocystis sp. PCC6803, corresponding to the Fd-binding site on PSI, was selected and targeted for the cross-linking with cytochrome c3 (cytc3) from Desulfovibrio vulgaris. The covalent adduct of cytc3 and PsaE was stoichiometrically assembled with PsaE-free PSI to form the cytc3/PSI complex. The NADPH production by the cytc3/PSI complex coupled with Fd and FNR decreased to approximately 20% of the original activity, whereas the H2 production by the cytc3/PSI complex coupled with hydrogenase from Desulfovibrio vulgaris was enhanced 7-fold. Consequently, in the simultaneous presence of hydrogenase, Fd, and FNR, the light-driven H2 production by the hydrogenase/cytc3/PSI complex was observed (0.30 pmol Hz/mg chlorophyll/h). These results suggest that the cytc3/PSI complex may produce H2 in vivo.
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Affiliation(s)
- Masaki Ihara
- Bioengineering, RIKEN, 2-1 Hirosawa, Wako 351-0198, Japan.
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28
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Ihara M, Nakamoto H, Kamachi T, Okura I, Maeda M. Photoinduced Hydrogen Production by Direct Electron Transfer from Photosystem I Cross-Linked with Cytochrome c3to [NiFe]-Hydrogenase. Photochem Photobiol 2006. [DOI: 10.1111/j.1751-1097.2006.tb09830.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Gitlin I, Carbeck JD, Whitesides GM. Warum sind Proteine geladen? Netzwerke aus Ladungs-Ladungs-Wechselwirkungen in Proteinen, analysiert über Ladungsleitern und Kapillarelektrophorese. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200502530] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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30
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Jolley C, Ben-Shem A, Nelson N, Fromme P. Structure of plant photosystem I revealed by theoretical modeling. J Biol Chem 2005; 280:33627-36. [PMID: 15955818 DOI: 10.1074/jbc.m500937200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Photosystem (PS) I is a large membrane protein complex vital for oxygenic photosynthesis, one of the most important biological processes on the planet. We present an "atomic" model of higher plant PSI, based on theoretical modeling using the recent 4.4 angstroms x-ray crystal structure of PSI from pea. Because of the lack of information on the amino acid side chains in the x-ray structural model and the high cofactor content in this system, novel modeling techniques were developed. Our model reveals some important structural features of plant PSI that were not visible in the crystal structure, and our model sheds light on the evolutionary relationship between plant and cyanobacterial PSI.
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Affiliation(s)
- Craig Jolley
- Department of Physics and Astronomy, Arizona State University, Tempe, Arizona 85281-1504, USA
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31
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Cassan N, Lagoutte B, Sétif P. Ferredoxin-NADP+ reductase. Kinetics of electron transfer, transient intermediates, and catalytic activities studied by flash-absorption spectroscopy with isolated photosystem I and ferredoxin. J Biol Chem 2005; 280:25960-72. [PMID: 15894798 DOI: 10.1074/jbc.m503742200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The electron transfer cascade from photosystem I to NADP+ was studied at physiological pH by flash-absorption spectroscopy in a Synechocystis PCC6803 reconstituted system comprised of purified photosystem I, ferredoxin, and ferredoxin-NADP+ reductase. Experiments were conducted with a 34-kDa ferredoxin-NADP+ reductase homologous to the chloroplast enzyme and a 38-kDa N-terminal extended form. Small differences in kinetic and catalytic properties were found for these two forms, although the largest one has a 3-fold decreased affinity for ferredoxin. The dissociation rate of reduced ferredoxin from photosystem I (800 s(-1)) and the redox potential of the first reduction of ferredoxin-NADP+ reductase (-380 mV) were determined. In the absence of NADP+, differential absorption spectra support the existence of a high affinity complex between oxidized ferredoxin and semireduced ferredoxin-NADP+ reductase. An effective rate of 140-170 s(-1) was also measured for the second reduction of ferredoxin-NADP+ reductase, this process having a rate constant similar to that of the first reduction. In the presence of NADP+, the second-order rate constant for the first reduction of ferredoxin-NADP+ reductase was 20% slower than in its absence, in line with the existence of ternary complexes (ferredoxin-NADP+ reductase)-NADP+-ferredoxin. A single catalytic turnover was monitored, with 50% NADP+ being reduced in 8-10 ms using 1.6 microM photosystem I. In conditions of multiple turnover, we determined initial rates of 360-410 electrons per s and per ferredox-in-NADP+ reductase for the reoxidation of 3.5 microM photoreduced ferredoxin. Identical rates were found with photosystem I lacking the PsaE subunit and wild type photosystem I. This suggests that, in contrast with previous proposals, the PsaE subunit is not involved in NADP+ photoreduction.
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Affiliation(s)
- Nicolas Cassan
- Service de Bioénergétique and CNRS URA 2096, Département de Biologie Joliot Curie, CEA Saclay, 91191 Gif sur Yvette, France
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32
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Wollenberg M, Berndt C, Bill E, Schwenn JD, Seidler A. A dimer of the FeS cluster biosynthesis protein IscA from cyanobacteria binds a [2Fe2S] cluster between two protomers and transfers it to [2Fe2S] and [4Fe4S] apo proteins. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:1662-71. [PMID: 12694179 DOI: 10.1046/j.1432-1033.2003.03522.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Two proteins with similarity to IscA are encoded in the genome of the cyanobacterium Synechocystis PCC 6803. One of them, the product of slr1417 which accounts for 0.025% of the total soluble protein of Synechocystis was over-expressed in E. coli and purified. The purified protein was found to be mainly dimeric and did not contain any cofactor. Incubation with iron ions, cysteine and Synechocystis IscS led to the formation of one [2Fe2S] cluster at an IscA dimer as demonstrated (by the binding of about one iron and one sulfide ion per IscA monomer) by UV/Vis, EPR and Mössbauer spectroscopy. Mössbauer spectroscopy further indicated that the FeS cluster was bound by four cysteine residues. Site-directed mutagenesis revealed that of the five cysteine residues only C110 and C112 were involved in cluster binding. It was therefore concluded that the [2Fe2S] cluster is located between the two protomers of the IscA dimer and ligated by C110 and C112 of both protomers. The cluster could be transferred to apo ferredoxin, a [2Fe2S] protein, with a half-time of 10 min. Surprisingly, incubation of cluster-containing IscA with apo adenosine 5'-phosphosulfate reductase led to a reactivation of the enzyme which requires the presence of a [4Fe4S] cluster. This demonstrates that it is possible to build [4Fe4S] clusters from [2Fe2S] units.
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Affiliation(s)
- Markus Wollenberg
- Biochemie der Pflanzen, Fakultät für Biologie, Ruhr-Universität Bochum, Germany
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33
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Sétif P, Fischer N, Lagoutte B, Bottin H, Rochaix JD. The ferredoxin docking site of photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1555:204-9. [PMID: 12206916 DOI: 10.1016/s0005-2728(02)00279-7] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction center of photosystem I (PSI) reduces soluble ferredoxin on the stromal side of the photosynthetic membranes of cyanobacteria and chloroplasts. The X-ray structure of PSI from the cyanobacterium Synechococcus elongatus has been recently established at a 2.5 A resolution [Nature 411 (2001) 909]. The kinetics of ferredoxin photoreduction has been studied in recent years in many mutants of the stromal subunits PsaC, PsaD and PsaE of PSI. We discuss the ferredoxin docking site of PSI using the X-ray structure and the effects brought by the PSI mutations to the ferredoxin affinity.
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Affiliation(s)
- Pierre Sétif
- CEA Saclay, Département de Biologie Joliot-Curie, Service de Bioénergétique and URA CNRS 2096, 91191 Gif sur Yvette, Cedex, France.
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Xu W, Tang H, Wang Y, Chitnis PR. Proteins of the cyanobacterial photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1507:32-40. [PMID: 11687206 DOI: 10.1016/s0005-2728(01)00208-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cyanobacterial photosystem (PS) I is remarkably similar to its counterpart in the chloroplast of plants and algae. Therefore, it has served as a prototype for the type I reaction centers of photosynthesis. Cyanobacterial PS I contains 11-12 proteins. Some of the cyanobacterial proteins are modified post-translationally. Reverse genetics has been used to generate subunit-deficient cyanobacterial mutants, phenotypes of which have revealed the functions of the missing proteins. The cyanobacterial PS I proteins bind cofactors, provide docking sites for electron transfer proteins, participate in tertiary and quaternary organization of the complex and protect the electron transfer centers. Many of these mutants are now being used in sophisticated structure-function analyses. Yet, the roles of some proteins of the cyanobacterial PS I are unknown. It is necessary to examine functions of these proteins on a global scale of cell physiology, biogenesis and evolution.
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Affiliation(s)
- W Xu
- Department of Biochemistry, Biophysics and Molecular Biology, 4156 Molecular Biology Building, Iowa State University, Ames, IA 50011, USA
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Abstract
Ferredoxin and flavodoxin are soluble proteins which are reduced by the terminal electron acceptors of photosystem I. The kinetics of ferredoxin (flavodoxin) photoreduction are discussed in detail, together with the last steps of intramolecular photosystem I electron transfer which precede ferredoxin (flavodoxin) reduction. The present knowledge concerning the photosystem I docking site for ferredoxin and flavodoxin is described in the second part of the review.
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Affiliation(s)
- P Sétif
- Section de Bioénergétique and CNRS URA 2096, Département de Biologie Cellulaire et Moléculaire, CEA Saclay, 91191, Gif sur Yvette, France.
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Chitnis PR. PHOTOSYSTEM I: Function and Physiology. ANNUAL REVIEW OF PLANT PHYSIOLOGY AND PLANT MOLECULAR BIOLOGY 2001; 52:593-626. [PMID: 11337410 DOI: 10.1146/annurev.arplant.52.1.593] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Photosystem I is the light-driven plastocyanin-ferredoxin oxidoreductase in the thylakoid membranes of cyanobacteria and chloroplasts. In recent years, sophisticated spectroscopy, molecular genetics, and biochemistry have been used to understand the light conversion and electron transport functions of photosystem I. The light-harvesting complexes and internal antenna of photosystem I absorb photons and transfer the excitation energy to P700, the primary electron donor. The subsequent charge separation and electron transport leads to the reduction of ferredoxin. The photosystem I proteins are responsible for the precise arrangement of cofactors and determine redox properties of the electron transfer centers. With the availability of genomic information and the structure of photosystem I, one can now probe the functions of photosystem I proteins and cofactors. The strong reductant produced by photosystem I has a central role in chloroplast metabolism, and thus photosystem I has a critical role in the metabolic networks and physiological responses in plants.
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Affiliation(s)
- Parag R Chitnis
- Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University, Ames, Iowa 50011; e-mail:
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Guillouard I, Lagoutte B, Moal G, Bottin H. Importance of the region including aspartates 57 and 60 of ferredoxin on the electron transfer complex with photosystem I in the cyanobacterium Synechocystis sp. PCC 6803. Biochem Biophys Res Commun 2000; 271:647-53. [PMID: 10814516 DOI: 10.1006/bbrc.2000.2687] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Ferredoxin reduction by photosystem I has been studied by flash-absorption spectroscopy. Aspartate residues 20, 57, and 60 of ferredoxin were changed to alanine, cysteine, arginine, or lysine. On the one hand, electron transfer from photosystem I to all mutated ferredoxins still occurs on a microsecond time scale, with half-times of ferredoxin reduction mostly conserved compared to wild-type ferredoxin. On the other hand, the total amplitude of the fast first-order reduction varies largely when residues 57 or 60 are modified, in apparent relation to the charge modification (neutralized or inverted). Substituting these two residues for lysine or arginine induce strong effects on ferredoxin binding (up to sixfold increase in K(D)), whereas the same substitution on aspartate 20, a spatially related residue, results in moderate effects (maximum twofold increase in K(D)). In addition, double mutations to arginine or lysine were performed on both aspartates 57 and 60. The mutated proteins have a 15- to 20-fold increased K(D) and show strong modifications in the amplitudes of the fast reduction kinetics. These results indicate that the acidic area of ferredoxin including aspartates 57 and 60, located opposite to the C-terminus, is crucial for high affinity interactions with photosystem I.
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Affiliation(s)
- I Guillouard
- CEA, Département de Biologie Cellulaire et Moléculaire, Section de Bioénergétique, CNRS URA 2096, CE de Saclay, Gif sur Yvette Cedex, 91191, France
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