1
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Chrysina M, Drosou M, Castillo RG, Reus M, Neese F, Krewald V, Pantazis DA, DeBeer S. Nature of S-States in the Oxygen-Evolving Complex Resolved by High-Energy Resolution Fluorescence Detected X-ray Absorption Spectroscopy. J Am Chem Soc 2023; 145:25579-25594. [PMID: 37970825 PMCID: PMC10690802 DOI: 10.1021/jacs.3c06046] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 10/13/2023] [Accepted: 10/13/2023] [Indexed: 11/19/2023]
Abstract
Photosystem II, the water splitting enzyme of photosynthesis, utilizes the energy of sunlight to drive the four-electron oxidation of water to dioxygen at the oxygen-evolving complex (OEC). The OEC harbors a Mn4CaO5 cluster that cycles through five oxidation states Si (i = 0-4). The S3 state is the last metastable state before the O2 evolution. Its electronic structure and nature of the S2 → S3 transition are key topics of persisting controversy. Most spectroscopic studies suggest that the S3 state consists of four Mn(IV) ions, compared to the Mn(III)Mn(IV)3 of the S2 state. However, recent crystallographic data have received conflicting interpretations, suggesting either metal- or ligand-based oxidation, the latter leading to an oxyl radical or a peroxo moiety in the S3 state. Herein, we utilize high-energy resolution fluorescence detected (HERFD) X-ray absorption spectroscopy to obtain a highly resolved description of the Mn K pre-edge region for all S-states, paying special attention to use chemically unperturbed S3 state samples. In combination with quantum chemical calculations, we achieve assignment of specific spectroscopic features to geometric and electronic structures for all S-states. These data are used to confidently discriminate between the various suggestions concerning the electronic structure and the nature of oxidation events in all observable catalytic intermediates of the OEC. Our results do not support the presence of either peroxo or oxyl in the active configuration of the S3 state. This establishes Mn-centered storage of oxidative equivalents in all observable catalytic transitions and constrains the onset of the O-O bond formation until after the final light-driven oxidation event.
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Affiliation(s)
- Maria Chrysina
- Max-Planck-Institut
für Chemische Energiekonversion, Stiftstr. 34-36, Mülheim
an der Ruhr 45470, Germany
- Institute
of Nanoscience & Nanotechnology, NCSR “Demokritos”, Athens 15310, Greece
| | - Maria Drosou
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr 45470, Germany
| | - Rebeca G. Castillo
- Max-Planck-Institut
für Chemische Energiekonversion, Stiftstr. 34-36, Mülheim
an der Ruhr 45470, Germany
- Laboratory
of Ultrafast Spectroscopy (LSU) and Lausanne Centre for Ultrafast
Science, École Polytechnique Fédérale
de Lausanne (EPFL), Lausanne CH-1015, Switzerland
| | - Michael Reus
- Max-Planck-Institut
für Chemische Energiekonversion, Stiftstr. 34-36, Mülheim
an der Ruhr 45470, Germany
| | - Frank Neese
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr 45470, Germany
| | - Vera Krewald
- Department
of Chemistry, Technical University of Darmstadt, Peter-Grünberg-Str. 4, Darmstadt 64287, Germany
| | - Dimitrios A. Pantazis
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, Mülheim an der Ruhr 45470, Germany
| | - Serena DeBeer
- Max-Planck-Institut
für Chemische Energiekonversion, Stiftstr. 34-36, Mülheim
an der Ruhr 45470, Germany
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2
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Lambertz J, Meier-Credo J, Kucher S, Bordignon E, Langer JD, Nowaczyk MM. Isolation of a novel heterodimeric PSII complex via strep-tagged PsbO. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2023; 1864:148953. [PMID: 36572329 DOI: 10.1016/j.bbabio.2022.148953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 11/28/2022] [Accepted: 12/14/2022] [Indexed: 12/24/2022]
Abstract
The multi-subunit membrane protein complex photosystem II (PSII) catalyzes the light-driven oxidation of water and with this the initial step of photosynthetic electron transport in plants, algae, and cyanobacteria. Its biogenesis is coordinated by a network of auxiliary proteins that facilitate the stepwise assembly of individual subunits and cofactors, forming various intermediate complexes until fully functional mature PSII is present at the end of the process. In the current study, we purified PSII complexes from a mutant line of the thermophilic cyanobacterium Thermosynechococcus vestitus BP-1 in which the extrinsic subunit PsbO, characteristic for active PSII, was fused with an N-terminal Twin-Strep-tag. Three distinct PSII complexes were separated by ion-exchange chromatography after the initial affinity purification. Two complexes differ in their oligomeric state (monomeric and dimeric) but share the typical subunit composition of mature PSII. They are characterized by the very high oxygen evolving activity of approx. 6000 μmol O2·(mg Chl·h)-1. Analysis of the third (heterodimeric) PSII complex revealed lower oxygen evolving activity of approx. 3000 μmol O2·(mg Chl·h)-1 and a manganese content of 2.7 (±0.2) per reaction center compared to 3.7 (±0.2) of fully active PSII. Mass spectrometry and time-resolved fluorescence spectroscopy further indicated that PsbO is partially replaced by Psb27 in this PSII fraction, thus implying a role of this complex in PSII repair.
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Affiliation(s)
- Jan Lambertz
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Jakob Meier-Credo
- Proteomics, Max Planck Institute of Biophysics, Max-von-Laue-Str. 3, 60438 Frankfurt am Main, Germany
| | - Svetlana Kucher
- Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany
| | - Enrica Bordignon
- Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany; Department of Physical Chemistry, University of Geneva, Quai Ernest Ansermet 30, 1211 Geneva, Switzerland(1)
| | - Julian D Langer
- Proteomics, Max Planck Institute of Biophysics, Max-von-Laue-Str. 3, 60438 Frankfurt am Main, Germany; Proteomics, Max Planck Institute for Brain Research, Max-von-Laue-Str. 4, 60438 Frankfurt am Main, Germany
| | - Marc M Nowaczyk
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany; Department of Biochemistry, University of Rostock, Albert-Einstein-Str. 3, 18059 Rostock, Germany(1).
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3
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Li J, Liang H, Li Y, Shi J. Interfacial assembly of photosystem II on nanotubular V2O5/TiO2 for photocurrent generation. Colloids Surf A Physicochem Eng Asp 2023. [DOI: 10.1016/j.colsurfa.2023.131230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
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4
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Lambertz J, Liauw P, Whitelegge JP, Nowaczyk MM. Mass spectrometry analysis of the photosystem II assembly factor Psb27 revealed variations in its lipid modification. PHOTOSYNTHESIS RESEARCH 2022; 152:305-316. [PMID: 34910272 PMCID: PMC9458691 DOI: 10.1007/s11120-021-00891-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 12/03/2021] [Indexed: 06/14/2023]
Abstract
The assembly of large, multi-cofactor membrane protein complexes like photosystem II (PSII) requires a high level of coordination. The process is facilitated by a large network of auxiliary proteins that bind transiently to unassembled subunits, preassembled modules or intermediate states of PSII, which are comprised of a subset of subunits. However, analysis of these immature, partially assembled PSII complexes is hampered by their low abundance and intrinsic instability. In this study, PSII was purified from the thermophilic cyanobacterium Thermosynechococcus elongatus via Twin-Strep-tagged CP43 and further separated by ion exchange chromatography into mature and immature complexes. Mass spectrometry analysis of the immature Psb27-PSII intermediate revealed six different Psb27 proteoforms with distinct lipid modifications. The maturation and functional role of thylakoid localized lipoproteins are discussed.
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Affiliation(s)
- Jan Lambertz
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany
| | - Pasqual Liauw
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany
| | - Julian P Whitelegge
- The Pasarow Mass Spectrometry Laboratory, David Geffen School of Medicine, The Jane and Terry Semel Institute for Neuroscience and Human Behavior, UCLA, Los Angeles, CA, 90095, USA
| | - Marc M Nowaczyk
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany.
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5
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Chang YS, Yang HC, Chao L. Formation of Supported Thylakoid Membrane Bioanodes for Effective Electron Transfer and Stable Photocurrent. ACS APPLIED MATERIALS & INTERFACES 2022; 14:22216-22224. [PMID: 35511069 DOI: 10.1021/acsami.2c04764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The light-dependent reactions of photosynthesis use light energy to generate photoelectrons traveling through the thylakoid membranes (TMs). Extracting the photoelectrons from the TMs to form bioanodes can have various applications. Most studies focus on modifying the electrode materials to increase the collected photocurrent. Seldom studies have investigated how the orientation of the TMs influences photocurrent collection. In addition, the formation of reactive oxygen species (ROS) during photosynthesis is a challenge for stable photocurrent generation. Here, we enhanced the photoelectron transfer from the TMs to electrodes by depositing expanded thylakoids as planar supported membranes onto an electrode. The high contact area between the external electrodes and TMs per unit mass of thylakoid allows the thylakoid to more effectively transfer electrons to the electrodes, thereby reducing the free electrons available for the ROS generation. We expanded the naturally stacked thylakoids into liposomes through osmotic pressure and dropcasted them onto an Au electrode. The electrochemical impedance measurement showed that the supported membrane bioanode formed by the expanded liposomes had a lower photoelectron transfer resistance. Additionally, we observed that the expanded TM bioanode provided a higher photocurrent and was more durable to air/water interfacial tension. These results suggest that the effective contact between the expanded TM and electrodes can lead to more efficient electron transfer and increase the system robustness. The photo fuel cell (PFC) made by the expanded TM bioanode had a higher open-circuit voltage than the one made by the stacked TM bioanode. Interestingly, we found that PFCs made of high-load TM bioanodes had fast photocurrent decay under continuous operation at high cell voltages. The poor contact of large numbers of TMs with the electrodes at the high-load TM bioanodes could cause more ROS accumulation and therefore decreased the operational stability, supporting the importance of effective contact between TMs and the electrodes.
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Affiliation(s)
- Yu-Shan Chang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Hao-Cin Yang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Ling Chao
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
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6
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Yu H, Hamaguchi T, Nakajima Y, Kato K, Kawakami K, Akita F, Yonekura K, Shen JR. Cryo-EM structure of monomeric photosystem II at 2.78 Å resolution reveals factors important for the formation of dimer. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2021; 1862:148471. [PMID: 34216574 DOI: 10.1016/j.bbabio.2021.148471] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 06/18/2021] [Accepted: 06/26/2021] [Indexed: 11/29/2022]
Abstract
Photosystem II (PSII) functions mainly as a dimer to catalyze the light energy conversion and water oxidation reactions. However, monomeric PSII also exists and functions in vivo in some cases. The crystal structure of monomeric PSII has been solved at 3.6 Å resolution, but it is still not clear which factors contribute to the formation of the dimer. Here, we solved the structure of PSII monomer at a resolution of 2.78 Å using cryo-electron microscopy (cryo-EM). From our cryo-EM density map, we observed apparent differences in pigments and lipids in the monomer-monomer interface between the PSII monomer and dimer. One β-carotene and two sulfoquinovosyl diacylglycerol (SQDG) molecules are found in the monomer-monomer interface of the dimer structure but not in the present monomer structure, although some SQDG and other lipid molecules are found in the analogous region of the low-resolution crystal structure of the monomer, or cryo-EM structure of an apo-PSII monomer lacking the extrinsic proteins from Synechocystis sp. PCC 6803. In the current monomer structure, a large part of the PsbO subunit was also found to be disordered. These results indicate the importance of the β-carotene, SQDG and PsbO in formation of the PSII dimer.
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Affiliation(s)
- Huaxin Yu
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima Naka, Okayama 700-8530, Japan; Department of Picobiology, Graduate School of Life Science, University of Hyogo, Hyogo 678-1297, Japan
| | - Tasuku Hamaguchi
- Biostructural Mechanism Laboratory, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Yoshiki Nakajima
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima Naka, Okayama 700-8530, Japan
| | - Koji Kato
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima Naka, Okayama 700-8530, Japan
| | - Keisuke Kawakami
- Biostructural Mechanism Laboratory, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Fusamichi Akita
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima Naka, Okayama 700-8530, Japan; Japan Science and Technology Agency, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
| | - Koji Yonekura
- Biostructural Mechanism Laboratory, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan; Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan; Advanced Electron Microscope Development Unit, RIKEN-JEOL Collaboration Center, RIKEN Baton Zone Program, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan.
| | - Jian-Ren Shen
- Research Institute for Interdisciplinary Science and Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima Naka, Okayama 700-8530, Japan.
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7
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Zabret J, Bohn S, Schuller SK, Arnolds O, Möller M, Meier-Credo J, Liauw P, Chan A, Tajkhorshid E, Langer JD, Stoll R, Krieger-Liszkay A, Engel BD, Rudack T, Schuller JM, Nowaczyk MM. Structural insights into photosystem II assembly. NATURE PLANTS 2021; 7:524-538. [PMID: 33846594 PMCID: PMC8094115 DOI: 10.1038/s41477-021-00895-0] [Citation(s) in RCA: 84] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 03/04/2021] [Indexed: 05/07/2023]
Abstract
Biogenesis of photosystem II (PSII), nature's water-splitting catalyst, is assisted by auxiliary proteins that form transient complexes with PSII components to facilitate stepwise assembly events. Using cryo-electron microscopy, we solved the structure of such a PSII assembly intermediate from Thermosynechococcus elongatus at 2.94 Å resolution. It contains three assembly factors (Psb27, Psb28 and Psb34) and provides detailed insights into their molecular function. Binding of Psb28 induces large conformational changes at the PSII acceptor side, which distort the binding pocket of the mobile quinone (QB) and replace the bicarbonate ligand of non-haem iron with glutamate, a structural motif found in reaction centres of non-oxygenic photosynthetic bacteria. These results reveal mechanisms that protect PSII from damage during biogenesis until water splitting is activated. Our structure further demonstrates how the PSII active site is prepared for the incorporation of the Mn4CaO5 cluster, which performs the unique water-splitting reaction.
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Affiliation(s)
- Jure Zabret
- Department of Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Stefan Bohn
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Sandra K Schuller
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
- CryoEM of Molecular Machines, SYNMIKRO Research Center and Department of Chemistry, Philipps University of Marburg, Marburg, Germany
| | - Oliver Arnolds
- Biomolecular Spectroscopy and RUBiospek|NMR, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Bochum, Germany
| | - Madeline Möller
- Department of Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | | | - Pasqual Liauw
- Department of Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany
| | - Aaron Chan
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology, Department of Biochemistry, and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Emad Tajkhorshid
- NIH Center for Macromolecular Modeling and Bioinformatics, Beckman Institute for Advanced Science and Technology, Department of Biochemistry, and Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, USA
| | - Julian D Langer
- Proteomics, Max Planck Institute of Biophysics, Frankfurt, Germany
- Proteomics, Max Planck Institute for Brain Research, Frankfurt, Germany
| | - Raphael Stoll
- Biomolecular Spectroscopy and RUBiospek|NMR, Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Bochum, Germany
| | - Anja Krieger-Liszkay
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, Gif-sur-Yvette, France
| | - Benjamin D Engel
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
- Helmholtz Pioneer Campus, Helmholtz Zentrum München, Neuherberg, Germany
- Department of Chemistry, Technical University of Munich, Garching, Germany
| | - Till Rudack
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Bochum, Germany.
- Department of Biophysics, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany.
| | - Jan M Schuller
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Martinsried, Germany.
- CryoEM of Molecular Machines, SYNMIKRO Research Center and Department of Chemistry, Philipps University of Marburg, Marburg, Germany.
| | - Marc M Nowaczyk
- Department of Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, Bochum, Germany.
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8
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Mascoli V, Bersanini L, Croce R. Far-red absorption and light-use efficiency trade-offs in chlorophyll f photosynthesis. NATURE PLANTS 2020; 6:1044-1053. [PMID: 32661277 DOI: 10.1038/s41477-020-0718-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 06/04/2020] [Indexed: 05/28/2023]
Abstract
Plants and cyanobacteria use the chlorophylls embedded in their photosystems to absorb photons and perform charge separation, the first step of converting solar energy to chemical energy. While oxygenic photosynthesis is primarily based on chlorophyll a photochemistry, which is powered by red light, a few cyanobacterial species can harness less energetic photons when growing in far-red light. Acclimatization to far-red light involves the incorporation of a small number of molecules of red-shifted chlorophyll f in the photosystems, whereas the most abundant pigment remains chlorophyll a. Due to its different energetics, chlorophyll f is expected to alter the excited-state dynamics of the photosynthetic units and, ultimately, their performances. Here we combined time-resolved fluorescence measurements on intact cells and isolated complexes to show that chlorophyll f insertion slows down the overall energy trapping in both photosystems. While this marginally affects the efficiency of photosystem I, it substantially decreases that of photosystem II. Nevertheless, we show that despite the lower energy output, the insertion of red-shifted chlorophylls in the photosystems remains advantageous in environments that are enriched in far-red light and therefore represents a viable strategy for extending the photosynthetically active spectrum in other organisms, including plants. However, careful design of the new photosynthetic units will be required to preserve their efficiency.
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Affiliation(s)
- Vincenzo Mascoli
- Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Faculty of Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Luca Bersanini
- Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Faculty of Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Roberta Croce
- Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Faculty of Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
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9
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Wang P, Zhao F, Hartmann V, Nowaczyk MM, Ruff A, Schuhmann W, Conzuelo F. Reassessing the rationale behind herbicide biosensors: The case of a photosystem II/redox polymer-based bioelectrode. Bioelectrochemistry 2020; 136:107597. [PMID: 32674005 DOI: 10.1016/j.bioelechem.2020.107597] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 07/04/2020] [Accepted: 07/04/2020] [Indexed: 01/12/2023]
Abstract
Interfacing photosynthetic protein complexes with electrodes is frequently used for the identification of electron transfer mechanisms and the fabrication of biosensors. Binding of herbicide compounds to the terminal plastoquinone QB at photosystem II (PSII) causes disruption of electron flow that is associated with a diminished performance of the associated biodevice. Thus, the principle of electron transport inhibition at PSII can be used for herbicide detection and has inspired the fabrication of several biosensors for this purpose. However, the biosensor performance may reveal a more complex behavior than generally expected. As we present here for a photobioelectrode constituted by PSII embedded in a redox polymer matrix, the effect caused by inhibitors does not only impact the electron transfer from PSII but also the properties of the polymer film used for immobilization and electrical wiring of the protein complexes. Incorporation of phenolic inhibitors into the polymer film surprisingly translates into enhanced photocurrents and, in particular cases, in a higher stability of the overall electrode architecture. The achieved results stress the importance to evaluate first the possible influence of analytes of interest on the biosensor architecture as a whole and provide important insights for consideration in future design of bioelectrochemical devices.
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Affiliation(s)
- Panpan Wang
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Fangyuan Zhao
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Volker Hartmann
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Marc M Nowaczyk
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Adrian Ruff
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Wolfgang Schuhmann
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany.
| | - Felipe Conzuelo
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780 Bochum, Germany.
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10
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Bobrowski T, Conzuelo F, Ruff A, Hartmann V, Frank A, Erichsen T, Nowaczyk MM, Schuhmann W. Scalable Fabrication of Biophotoelectrodes by Means of Automated Airbrush Spray-Coating. Chempluschem 2020; 85:1396-1400. [PMID: 32608194 DOI: 10.1002/cplu.202000291] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 06/05/2020] [Indexed: 11/07/2022]
Abstract
The fabrication and electrochemical evaluation of transparent photoelectrodes consisting of Photosystem I (PSI) or Photosystem II (PSII) is described, which are embedded and electrically wired by a redox polymer. The fabrication process is performed by an automated airbrush-type spray coating system, which ensures controlled and scalable electrode preparation. As proof of concept, electrodes with a surface area of up to 25 cm2 were prepared. The macro-porous structure of the indium tin oxide electrodes allows a high loading of the photoactive protein complexes leading to enhanced photocurrents, which are essential for potentially technologically relevant solar-powered devices. In addition, we show that unpurified crude PSII extracts, which can be provided in comparatively high yields for electrode modification, are suitable for photoelectrode fabrication with comparable photocurrent densities.
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Affiliation(s)
- Tim Bobrowski
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Felipe Conzuelo
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Adrian Ruff
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Volker Hartmann
- Plant Biochemistry; Faculty of Biology and Biotechnology, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Anna Frank
- Plant Biochemistry; Faculty of Biology and Biotechnology, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Thomas Erichsen
- Sensolytics GmbH, Universitätsstr. 142, 44799, Bochum, Germany
| | - Marc M Nowaczyk
- Plant Biochemistry; Faculty of Biology and Biotechnology, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Wolfgang Schuhmann
- Analytical Chemistry - Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
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11
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Zhang JZ, Reisner E. Advancing photosystem II photoelectrochemistry for semi-artificial photosynthesis. Nat Rev Chem 2019. [DOI: 10.1038/s41570-019-0149-4] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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12
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Zhao F, Bobrowski T, Ruff A, Hartmann V, Nowaczyk MM, Rögner M, Conzuelo F, Schuhmann W. A light-driven Nernstian biosupercapacitor. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2019.03.168] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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13
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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: 127] [Impact Index Per Article: 21.2] [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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14
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Kawakami K, Shen JR. Purification of fully active and crystallizable photosystem II from thermophilic cyanobacteria. Methods Enzymol 2018; 613:1-16. [PMID: 30509462 DOI: 10.1016/bs.mie.2018.10.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Photosystem II (PSII) is a membrane protein complex which functions to catalyze light-induced water oxidation in oxygenic photosynthesis. Through the water-splitting reaction of PSII, light energy is converted into biologically useful chemical energy, and molecular oxygen is formed which transformed the atmosphere into an aerobic one and sustained aerobic life on the Earth. The PSII core complex from cyanobacteria consists of 17 transmembrane subunits and 3 extrinsic subunits with a total molecular mass of approximately 350kDa per monomer, and PSII exists predominately in a dimeric form in vivo. This chapter describes the purification procedures leading to highly pure, homogenous, and highly active PSII core dimers from a thermophilic cyanobacterium, Thermosynechococcus vulcanus (T. vulcanus), that are used for successful crystallization and diffraction at atomic resolution. The purity and homogeneity of the PSII dimers thus obtained are characterized by absorption spectra, low-temperature fluorescence spectra, SDS-PAGE, clear native PAGE, blue native PAGE, gel filtration chromatography, and oxygen-evolving activity measurements. Finally, high-quality crystals obtained from the purified PSII dimers are shown.
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Affiliation(s)
- Keisuke Kawakami
- The OCU Advanced Research Institute for Natural Science & Technology (OCARINA), Osaka City University, Osaka, Japan
| | - Jian-Ren Shen
- Graduate School of Natural Science and Technology, Okayama University, Okayama, Japan.
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15
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Zhao F, Hartmann V, Ruff A, Nowaczyk MM, Rögner M, Schuhmann W, Conzuelo F. Unravelling electron transfer processes at photosystem 2 embedded in an Os-complex modified redox polymer. Electrochim Acta 2018. [DOI: 10.1016/j.electacta.2018.09.093] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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16
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Abstract
X-ray scattering is uniquely suited to the study of disordered systems and thus has the potential to provide insight into dynamic processes where diffraction methods fail. In particular, while X-ray crystallography has been a staple of structural biology for more than half a century and will continue to remain so, a major limitation of this technique has been the lack of dynamic information. Solution X-ray scattering has become an invaluable tool in structural and mechanistic studies of biological macromolecules where large conformational changes are involved. Such systems include allosteric enzymes that play key roles in directing metabolic fluxes of biochemical pathways, as well as large, assembly-line type enzymes that synthesize secondary metabolites with pharmaceutical applications. Furthermore, crystallography has the potential to provide information on protein dynamics via the diffuse scattering patterns that are overlaid with Bragg diffraction. Historically, these patterns have been very difficult to interpret, but recent advances in X-ray detection have led to a renewed interest in diffuse scattering analysis as a way to probe correlated motions. Here, we will review X-ray scattering theory and highlight recent advances in scattering-based investigations of protein solutions and crystals, with a particular focus on complex enzymes.
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Affiliation(s)
- Steve P Meisburger
- Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States
| | - William C Thomas
- Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States
| | - Maxwell B Watkins
- Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States
| | - Nozomi Ando
- Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States
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17
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Eßmann V, Zhao F, Hartmann V, Nowaczyk MM, Schuhmann W, Conzuelo F. In Operando Investigation of Electrical Coupling of Photosystem 1 and Photosystem 2 by Means of Bipolar Electrochemistry. Anal Chem 2017; 89:7160-7165. [DOI: 10.1021/acs.analchem.7b01222] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Vera Eßmann
- Analytical
Chemistry - Center for Electrochemical Sciences (CES) and ‡Plant Biochemistry, Ruhr-Universität Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Fangyuan Zhao
- Analytical
Chemistry - Center for Electrochemical Sciences (CES) and ‡Plant Biochemistry, Ruhr-Universität Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Volker Hartmann
- Analytical
Chemistry - Center for Electrochemical Sciences (CES) and ‡Plant Biochemistry, Ruhr-Universität Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Marc M. Nowaczyk
- Analytical
Chemistry - Center for Electrochemical Sciences (CES) and ‡Plant Biochemistry, Ruhr-Universität Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Wolfgang Schuhmann
- Analytical
Chemistry - Center for Electrochemical Sciences (CES) and ‡Plant Biochemistry, Ruhr-Universität Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
| | - Felipe Conzuelo
- Analytical
Chemistry - Center for Electrochemical Sciences (CES) and ‡Plant Biochemistry, Ruhr-Universität Bochum, Universitätsstr. 150, D-44780 Bochum, Germany
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18
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Yoneda Y, Katayama T, Nagasawa Y, Miyasaka H, Umena Y. Dynamics of Excitation Energy Transfer Between the Subunits of Photosystem II Dimer. J Am Chem Soc 2016; 138:11599-605. [DOI: 10.1021/jacs.6b04316] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yusuke Yoneda
- Graduate
School of Engineering Science, Osaka University, Toyonaka, Osaka560-8531, Japan
| | - Tetsuro Katayama
- Graduate
School of Engineering Science, Osaka University, Toyonaka, Osaka560-8531, Japan
| | - Yutaka Nagasawa
- Graduate
School of Engineering Science, Osaka University, Toyonaka, Osaka560-8531, Japan
- College
of Life Science, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan
- PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan
| | - Hiroshi Miyasaka
- Graduate
School of Engineering Science, Osaka University, Toyonaka, Osaka560-8531, Japan
| | - Yasufumi Umena
- Research
Institute for Interdisciplinary Science, Okayama University, Kita-ku, Okayama 700-8530, Japan
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19
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Hynninen PH, Mesilaakso M. Synthesis and characterization of chlorophyll a enol derivatives: Chlorophyll a tert-butyldimethylsilyl-enol ether and 131-deoxo-131, 132-didehydro-chlorophyll a. J PORPHYR PHTHALOCYA 2016. [DOI: 10.1142/s1088424616500486] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Using the sterically hindered base, 1,8-diazabicyclo[5.4.0]undec-7-ene, for enolization and tert-butyldimethylsilyl-trifluoromethanesulfonate for silylation, chlorophyll (Chl) [Formula: see text] produced after 15 min at 0 [Formula: see text]C in deaerated pyridine solution under argon, after work-up and chromatographic purification on a sucrose column, tert-butyldimethylsilyl-enol ether of Chl [Formula: see text] in a yield of 77%. The 131-deoxo-131,132-didehydro-chlorophyll [Formula: see text], was obtained in a yield of 23% through a reaction sequence, where Chl [Formula: see text] was first reduced with sodium borohydride to 13[Formula: see text]-hydroxy-Chl [Formula: see text], which via demetalation yielded 13[Formula: see text]-hydroxypheophytin [Formula: see text]. In the presence of the sterically hindered base, 1,8-bis(dimethylamino)naphthalene, trifluoroacetylimidazole dehydrated 13[Formula: see text]-hydroxypheophytin [Formula: see text] to 131-deoxo-131,132-didehydro-pheophytin [Formula: see text], which after metalation yielded 131-deoxo-131,132-didehydro-Chl [Formula: see text]. Using 1,8-bis(dimethylamino)naphthalene and trifluoroacetylimidazole, the straight conversion of 13[Formula: see text]-hydroxy-Chl [Formula: see text] to 131-deoxo-131,132-didehydro-Chl [Formula: see text] was found unsuccessful. The major products were characterized by electronic absorption spectra (UV-vis) and practically completely assigned 1H and [Formula: see text]C NMR spectra. Some intermediates of the syntheses were also characterized by ESI-TOF mass spectra. Compared with Chl [Formula: see text], the macrocyclic ring-current in the synthesized Chl [Formula: see text] enol derivatives was found weakened by the expansion of the [Formula: see text]-system to include the isocyclic ring E. Nevertheless, these enol derivatives were still considered to be diamagnetic and aromatic. The possibility of the functional role of the enol derivatives of chlorophyll in photosynthesis is discussed.
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Affiliation(s)
- Paavo H. Hynninen
- Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, P.O. Box 56 (Viikinkaari 5 E), FI-00014 Helsinki, Finland
| | - Markku Mesilaakso
- Finnish Institute for Verification of the Chemical Weapons Convention, University of Helsinki, P.O. Box 55 (A.I. Virtasen Aukio 1), FI-00014 Helsinki, Finland
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20
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Cormann KU, Möller M, Nowaczyk MM. Critical Assessment of Protein Cross-Linking and Molecular Docking: An Updated Model for the Interaction Between Photosystem II and Psb27. FRONTIERS IN PLANT SCIENCE 2016; 7:157. [PMID: 26925076 PMCID: PMC4758025 DOI: 10.3389/fpls.2016.00157] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 01/30/2016] [Indexed: 05/09/2023]
Abstract
Photosystem II (PSII) is a large membrane-protein complex composed of about 20 subunits and various cofactors, which mediates the light-driven oxidation of water and reduction of plastoquinone, and is part of the photosynthetic electron transfer chain that is localized in the thylakoid membrane of cyanobacteria, algae, and plants. The stepwise assembly of PSII is guided and facilitated by numerous auxiliary proteins that play specific roles in this spatiotemporal process. Psb27, a small protein localized in the thylakoid lumen, appears to associate with an intermediate PSII complex that is involved in assembly of the Mn4CaO5 cluster. Its precise binding position on the PSII intermediate remains elusive, as previous approaches to the localization of Psb27 on PSII have yielded contradictory results. This was our motivation for a critical assessment of previously used methods and the development of an improved analysis pipeline. The combination of chemical cross-linking and mass spectrometry (CX-MS) with isotope-coded cross-linkers was refined and validated with reference to the PSII crystal structure. Psb27 was localized on the PSII surface adjacent to the large lumenal domain of CP43 on the basis of a cross-link connecting Psb27-K91 to CP43-K381. Additional contacts associating Psb27 with CP47 and the C-termini of D1 and D2 were detected by surface plasmon resonance (SPR) spectroscopy. This information was used to model the binding of Psb27 to the PSII surface in a region that is occupied by PsbV in the mature complex.
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21
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Plumeré N, Nowaczyk MM. Biophotoelectrochemistry of Photosynthetic Proteins. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2016; 158:111-136. [DOI: 10.1007/10_2016_7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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22
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Heinz S, Liauw P, Nickelsen J, Nowaczyk M. Analysis of photosystem II biogenesis in cyanobacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1857:274-87. [PMID: 26592144 DOI: 10.1016/j.bbabio.2015.11.007] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Revised: 11/13/2015] [Accepted: 11/15/2015] [Indexed: 11/25/2022]
Abstract
Photosystem II (PSII), a large multisubunit membrane protein complex found in the thylakoid membranes of cyanobacteria, algae and plants, catalyzes light-driven oxygen evolution from water and reduction of plastoquinone. Biogenesis of PSII requires coordinated assembly of at least 20 protein subunits, as well as incorporation of various organic and inorganic cofactors. The stepwise assembly process is facilitated by numerous protein factors that have been identified in recent years. Further analysis of this process requires the development or refinement of specific methods for the identification of novel assembly factors and, in particular, elucidation of the unique role of each. Here we summarize current knowledge of PSII biogenesis in cyanobacteria, focusing primarily on the impact of methodological advances and innovations. This article is part of a Special Issue entitled Organization and dynamics of bioenergetic systems in bacteria, edited by Conrad Mullineaux.
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Affiliation(s)
- Steffen Heinz
- Molekulare Pflanzenwissenschaften, Biozentrum LMU München, Großhaderner Str. 2-4, 82152 Planegg-Martinsried, Germany
| | - Pasqual Liauw
- Biochemie der Pflanzen, Ruhr Universität Bochum, Universitätsstr. 150, 44801 Bochum, Germany
| | - Jörg Nickelsen
- Molekulare Pflanzenwissenschaften, Biozentrum LMU München, Großhaderner Str. 2-4, 82152 Planegg-Martinsried, Germany.
| | - Marc Nowaczyk
- Biochemie der Pflanzen, Ruhr Universität Bochum, Universitätsstr. 150, 44801 Bochum, Germany.
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23
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Simultaneous measurements of photocurrents and H2O2 evolution from solvent exposed photosystem 2 complexes. Biointerphases 2015; 11:019001. [PMID: 26700470 DOI: 10.1116/1.4938090] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
In plants, algae, and cyanobacteria, photosystem 2 (PS2) catalyzes the light driven oxidation of water. The main products of this reaction are protons and molecular oxygen. In vitro, however, it was demonstrated that reactive oxygen species like hydrogen peroxide are obtained as partially reduced side products. The transition from oxygen to hydrogen peroxide evolution might be induced by light triggered degradation of PS2's active center. Herein, the authors propose an analytical approach to investigate light induced bioelectrocatalytic processes such as PS2 catalyzed water splitting. By combining chronoamperometry and fluorescence microscopy, the authors can simultaneously monitor the photocurrent and the hydrogen peroxide evolution of light activated, solvent exposed PS2 complexes, which have been immobilized on a functionalized gold electrode. The authors show that under limited electron mediation PS2 displays a lower photostability that correlates with an enhanced H2O2 generation as a side product of the light induced water oxidation.
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24
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Shen JR. The Structure of Photosystem II and the Mechanism of Water Oxidation in Photosynthesis. ANNUAL REVIEW OF PLANT BIOLOGY 2015; 66:23-48. [PMID: 25746448 DOI: 10.1146/annurev-arplant-050312-120129] [Citation(s) in RCA: 453] [Impact Index Per Article: 50.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Oxygenic photosynthesis forms the basis of aerobic life on earth by converting light energy into biologically useful chemical energy and by splitting water to generate molecular oxygen. The water-splitting and oxygen-evolving reaction is catalyzed by photosystem II (PSII), a huge, multisubunit membrane-protein complex located in the thylakoid membranes of organisms ranging from cyanobacteria to higher plants. The structure of PSII has been analyzed at 1.9-Å resolution by X-ray crystallography, revealing a clear picture of the Mn4CaO5 cluster, the catalytic center for water oxidation. This article provides an overview of the overall structure of PSII followed by detailed descriptions of the specific structure of the Mn4CaO5 cluster and its surrounding protein environment. Based on the geometric organization of the Mn4CaO5 cluster revealed by the crystallographic analysis, in combination with the results of a vast number of experimental studies involving spectroscopic and other techniques as well as various theoretical studies, the article also discusses possible mechanisms for water splitting that are currently under consideration.
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Affiliation(s)
- Jian-Ren Shen
- Photosynthesis Research Center, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan;
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25
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Cormann KU, Bartsch M, Rögner M, Nowaczyk MM. Localization of the CyanoP binding site on photosystem II by surface plasmon resonance spectroscopy. FRONTIERS IN PLANT SCIENCE 2014; 5:595. [PMID: 25414711 PMCID: PMC4220643 DOI: 10.3389/fpls.2014.00595] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 10/13/2014] [Indexed: 05/23/2023]
Abstract
Photosystem II (PSII), a large multi subunit membrane protein complex localized in the thylakoid membrane of cyanobacteria and chloroplasts, is the only known enzyme that catalyzes the light-driven oxidation of water. In addition to the membrane intrinsic part of PSII, efficient oxygen evolution requires soluble protein subunits at its luminal interface. In contrast to the detailed crystal structure of the active cyanobacterial complex the characterization of intermediate PSII species related to its assembly and repair is hampered by their instability or low abundance. As most structural variations of the corresponding PSII species are based on a different set of protein factors bound to the luminal interface of the complex we developed a system for interaction analysis between PSII and its soluble interaction partners based on surface plasmon resonance (SPR) spectroscopy. The assay was validated by the correct localization of the extrinsic PSII proteins PsbO, PsbV, and PsbU on the luminal PSII surface and used to determine the unknown binding position of CyanoP, the cyanobacterial homolog of higher plant PsbP. The CyanoP binding site was clearly localized in the center of PSII at a position, which is occupied by the PsbO subunit in mature PSII complexes. Consistently, we demonstrate selective binding of CyanoP to an inactive PSII assembly intermediate that lacks the extrinsic subunits PsbO, PsbV, and PsbU. These findings suggest, that CyanoP functions in the dynamic lifecycle of PSII, possibly in the association of CP47 and CP43 or in photoactivation of the oxygen-evolving complex.
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Affiliation(s)
| | | | | | - Marc M. Nowaczyk
- *Correspondence: Marc M. Nowaczyk, Plant Biochemistry, Ruhr University Bochum, Universitätsstraße 150, 44801 Bochum, Germany e-mail:
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26
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Wulfhorst H, Franken LE, Wessinghage T, Boekema EJ, Nowaczyk MM. The 5 kDa protein NdhP is essential for stable NDH-1L assembly in Thermosynechococcus elongatus. PLoS One 2014; 9:e103584. [PMID: 25119998 PMCID: PMC4131877 DOI: 10.1371/journal.pone.0103584] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 07/02/2014] [Indexed: 12/24/2022] Open
Abstract
The cyanobacterial NADPH:plastoquinone oxidoreductase complex (NDH-1), that is related to Complex I of eubacteria and mitochondria, plays a pivotal role in respiration as well as in cyclic electron transfer (CET) around PSI and is involved in a unique carbon concentration mechanism (CCM). Despite many achievements in the past, the complex protein composition and the specific function of many subunits of the different NDH-1 species remain elusive. We have recently discovered in a NDH-1 preparation from Thermosynechococcus elongatus two novel single transmembrane peptides (NdhP, NdhQ) with molecular weights below 5 kDa. Here we show that NdhP is a unique component of the ∼450 kDa NDH-1L complex, that is involved in respiration and CET at high CO2 concentration, and not detectable in the NDH-1MS and NDH-1MS' complexes that play a role in carbon concentration. C-terminal fusion of NdhP with his-tagged superfolder GFP and the subsequent analysis of the purified complex by electron microscopy and single particle averaging revealed its localization in the NDH-1L specific distal unit of the NDH-1 complex, that is formed by the subunits NdhD1 and NdhF1. Moreover, NdhP is essential for NDH-1L formation, as this type of NDH-1 was not detectable in a ΔndhP::Km mutant.
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Affiliation(s)
- Hannes Wulfhorst
- Department of Plant Biochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Linda E. Franken
- Electron Microscopy Department, University of Groningen, Groningen, The Netherlands
| | - Thomas Wessinghage
- Department of Plant Biochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Egbert J. Boekema
- Electron Microscopy Department, University of Groningen, Groningen, The Netherlands
| | - Marc M. Nowaczyk
- Department of Plant Biochemistry, Ruhr-University Bochum, Bochum, Germany
- * E-mail:
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27
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Metabolic engineering of cyanobacteria for the production of hydrogen from water. Biochem Soc Trans 2014; 41:1254-9. [PMID: 24059516 DOI: 10.1042/bst20130122] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Requirements concerning the construction of a minimal photosynthetic design cell with direct coupling of water-splitting photosynthesis and H2 production are discussed in the present paper. Starting from a cyanobacterial model cell, Synechocystis PCC 6803, potentials and possible limitations are outlined and realization strategies are presented. In extension, the limits of efficiency of all major biological components can be approached in a semi-artificial system consisting of two electrochemically coupled half-cells without the physiological constraints of a living cell.
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28
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Cimdins A, Klinkert B, Aschke-Sonnenborn U, Kaiser FM, Kortmann J, Narberhaus F. Translational control of small heat shock genes in mesophilic and thermophilic cyanobacteria by RNA thermometers. RNA Biol 2014; 11:594-608. [PMID: 24755616 PMCID: PMC4152365 DOI: 10.4161/rna.28648] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Cyanobacteria constitute a heterogeneous phylum of oxygen-producing, photosynthetic prokaryotes. They are susceptible to various stress conditions like heat, salt, or light stress, all inducing the cyanobacterial heat shock response (HSR). Cyanobacterial small heat shock proteins (sHsps) are known to preserve thylakoid membrane integrity under stress conditions, thereby protecting the photosynthesis machinery. In Synechocystis sp PCC 6803, synthesis of the sHsp Hsp17 is regulated by an RNA thermometer (RNAT) in the 5′-untranslated region (5′-UTR) of the hsp17 mRNA. RNATs are direct temperature sensors that control expression of many bacterial heat shock and virulence genes. They hinder translation at low temperatures by base pairing, thus blocking ribosome access to the mRNA.
To explore the temperature range in which RNATs act, we studied various RNAT candidates upstream of sHsp genes from mesophilic and thermophilic cyanobacteria. The mesophilic cyanobacteria Anabaena variabilis and Nostoc sp chromosomally encode two sHsps each. Reporter gene studies suggested RNAT-mediated post-transcriptional regulation of shsp expression in both organisms. Detailed structural analysis of the two A. variabilis candidates revealed two novel RNAT types. The first, avashort, regulates translation primarily by masking of the AUG translational start codon. The second, featuring an extended initial hairpin, thus named avalong, presumably makes use of complex tertiary interaction. The 5′-UTR of the small heat shock gene hspA in the thermophile Thermosynechococcus elongatus is predicted to adopt an extended secondary structure. Structure probing revealed that the ribosome binding site was blocked at temperatures below 55 °C. The results of this study demonstrate that cyanobacteria commonly use RNATs to control expression of their small heat shock genes.
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Affiliation(s)
- Annika Cimdins
- Microbial Biology; Ruhr University Bochum; Bochum, Germany
| | | | | | | | - Jens Kortmann
- Microbial Biology; Ruhr University Bochum; Bochum, Germany
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29
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Hartmann V, Kothe T, Pöller S, El-Mohsnawy E, Nowaczyk MM, Plumeré N, Schuhmann W, Rögner M. Redox hydrogels with adjusted redox potential for improved efficiency in Z-scheme inspired biophotovoltaic cells. Phys Chem Chem Phys 2014; 16:11936-41. [DOI: 10.1039/c4cp00380b] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kothe T, Plumeré N, Badura A, Nowaczyk MM, Guschin DA, Rögner M, Schuhmann W. Combination of a photosystem 1-based photocathode and a photosystem 2-based photoanode to a Z-scheme mimic for biophotovoltaic applications. Angew Chem Int Ed Engl 2013; 52:14233-6. [PMID: 24323676 PMCID: PMC4230396 DOI: 10.1002/anie.201303671] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 07/13/2013] [Indexed: 12/22/2022]
Affiliation(s)
- Tim Kothe
- Plant Biochemistry, Ruhr-Universität BochumUniversitätsstrasse 150, 44780 Bochum (Germany)
| | - Nicolas Plumeré
- Analytische Chemie—Elektroanalytik & Sensorik and Center for Electrochemical Sciences—CESRuhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum (Germany)
| | - Adrian Badura
- Plant Biochemistry, Ruhr-Universität BochumUniversitätsstrasse 150, 44780 Bochum (Germany)
| | - Marc M Nowaczyk
- Plant Biochemistry, Ruhr-Universität BochumUniversitätsstrasse 150, 44780 Bochum (Germany)
| | - Dmitrii A Guschin
- Analytische Chemie—Elektroanalytik & Sensorik and Center for Electrochemical Sciences—CESRuhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum (Germany)
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Kothe T, Plumeré N, Badura A, Nowaczyk MM, Guschin DA, Rögner M, Schuhmann W. Die Kombination einer auf Photosystem 1 basierenden Photokathode und einer auf Photosystem 2 basierenden Photoanode zu einem Z-Schema-Analogon für biophotovoltaische Anwendungen. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201303671] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kawakami K, Umena Y, Iwai M, Kawabata Y, Ikeuchi M, Kamiya N, Shen JR. Roles of PsbI and PsbM in photosystem II dimer formation and stability studied by deletion mutagenesis and X-ray crystallography. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1807:319-25. [DOI: 10.1016/j.bbabio.2010.12.013] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 12/15/2010] [Accepted: 12/16/2010] [Indexed: 02/03/2023]
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Sander J, Nowaczyk M, Buchta J, Dau H, Vass I, Deák Z, Dorogi M, Iwai M, Rögner M. Functional characterization and quantification of the alternative PsbA copies in Thermosynechococcus elongatus and their role in photoprotection. J Biol Chem 2010; 285:29851-6. [PMID: 20663887 DOI: 10.1074/jbc.m110.127142] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The D1 protein (PsbA) of photosystem II (PSII) from Thermosynechococcus elongatus is encoded by a psbA gene family that is typical of cyanobacteria. Although the transcription of these three genes has been studied previously (Kós, P. B., Deák, Z., Cheregi, O., and Vass, I. (2008) Biochim. Biophys. Acta 1777, 74-83), the protein quantification had not been possible due to the high sequence identity between the three PsbA copies. The successful establishment of a method to quantify the PsbA proteins on the basis of reverse phase-LC-electrospray mass ionization-MS/MS (RP-LC-ESI-MS/MS) enables an accurate comparison of transcript and protein level for the first time ever. Upon high light incubation, about 70% PsbA3 could be detected, which closely corresponds to the transcript level. It was impossible to detect any PsbA2 under all tested conditions. The construction of knock-out mutants enabled for the first time a detailed characterization of both whole cells and also isolated PSII complexes. PSII complexes of the ΔpsbA1/psbA2 mutant contained only copy PsbA3, whereas only PsbA1 could be detected in PSII complexes from the ΔpsbA3 mutant. In whole cells as well as in isolated complexes, a shift of the free energy between the redox pairs in the PsbA3 complexes in comparison with PsbA1 could be detected by thermoluminescence and delayed fluorescence measurements. This change is assigned to a shift of the redox potential of pheophytin toward more positive values. Coincidentally, no differences in the Q(A)-Q(B) electron transfer could be observed in flash-induced fluorescence decay or prompt fluorescence measurements. In conclusion, PsbA3 complexes yield a better protection against photoinhibition due to a higher probability of the harmless dissipation of excess energy.
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Affiliation(s)
- Julia Sander
- Plant Biochemistry, Ruhr-University Bochum, D-44780 Bochum, Germany
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Takahashi T, Inoue-Kashino N, Ozawa SI, Takahashi Y, Kashino Y, Satoh K. Photosystem II complex in vivo is a monomer. J Biol Chem 2009; 284:15598-606. [PMID: 19351885 PMCID: PMC2708856 DOI: 10.1074/jbc.m109.000372] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Revised: 04/05/2009] [Indexed: 11/06/2022] Open
Abstract
Photosystem II (PS II) complexes are membrane protein complexes that are composed of >20 distinct subunit proteins. Similar to many other membrane protein complexes, two PS II complexes are believed to form a homo-dimer whose molecular mass is approximately 650 kDa. Contrary to this well known concept, we propose that the functional form of PS II in vivo is a monomer, based on the following observations. Deprivation of lipids caused the conversion of PS II from a monomeric form to a dimeric form. Only a monomeric PS II was detected in solubilized cyanobacterial and red algal thylakoids using blue-native polyacrylamide gel electrophoresis. Furthermore, energy transfer between PS II units, which was observed in the purified dimeric PS II, was not detected in vivo. Our proposal will lead to a re-evaluation of many crystallographic models of membrane protein complexes in terms of their oligomerization status.
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Affiliation(s)
- Takeshi Takahashi
- From the Graduate School of Life Science, University of Hyogo, 3-2-1 Kohto, Kamigohri, Ako-gun, Hyogo 678-1297 and the
| | - Natsuko Inoue-Kashino
- From the Graduate School of Life Science, University of Hyogo, 3-2-1 Kohto, Kamigohri, Ako-gun, Hyogo 678-1297 and the
- Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Okayama 700-8530, Japan
| | - Shin-ichiro Ozawa
- Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Okayama 700-8530, Japan
| | - Yuichiro Takahashi
- Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-Naka, Okayama 700-8530, Japan
| | - Yasuhiro Kashino
- From the Graduate School of Life Science, University of Hyogo, 3-2-1 Kohto, Kamigohri, Ako-gun, Hyogo 678-1297 and the
| | - Kazuhiko Satoh
- From the Graduate School of Life Science, University of Hyogo, 3-2-1 Kohto, Kamigohri, Ako-gun, Hyogo 678-1297 and the
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Slavov C, El-Mohsnawy E, Rögner M, Holzwarth AR. Trapping kinetics in isolated cyanobacterial PS I complexes. Chem Phys 2009. [DOI: 10.1016/j.chemphys.2008.12.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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36
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Towards structural elucidation of eukaryotic photosystem II: Purification, crystallization and preliminary X-ray diffraction analysis of photosystem II from a red alga. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1787:121-8. [DOI: 10.1016/j.bbabio.2008.11.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Revised: 11/06/2008] [Accepted: 11/07/2008] [Indexed: 11/23/2022]
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Viruvuru V, Fragata M. Photochemical cooperativity in photosystem II. Characterization of oxygen evolution discontinuities in the light-response curves. Phys Chem Chem Phys 2008; 10:6607-14. [PMID: 18989471 DOI: 10.1039/b809294j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In two previous papers (Fragata et al., J. Phys. Chem. B, 2005, 109, 14707-14714; Fragata et al., J. Phys. Chem. B, 2007, 111, 3315-3320), it was shown that the variation of oxygen evolution with the light intensity (I) in photosystem II (PSII) in steady state conditions can be formulated according to the Langmuir adsorption isotherm for heterogeneous catalysis. This yielded the expression OEth = OEth(max) I/(L1/2 + I), where OEth is the theoretical oxygen evolution, OEth(max) the maximum oxygen evolution, and L1/2 the irradiance giving OEth(max)/2. In this approximation, the photons interaction with the chlorophylls in the PSII reaction center is assumed to be a heterogeneous reaction in which the light is represented as a stream of particles instead of an electromagnetic wave. That is, the chlorophyll molecules are the adsorption surfaces (or heterogeneous catalysts), and the incident (or exciting) photons are the substrate, or the reagent. Recently, the examination of new experimental data obtained with 2,6-dichloro-p-benzoquinone (DCBQ) and p-benzoquinone (pBQ) as exogenous electron acceptors, disclosed the presence of oxygen evolution discontinuities (or transitions) in the light-response curves. The new data were fitted with a mathematical summation of hyperbola of order n(i) > 1, OEth = Sigma(i) [OEth(max)]iIn(i)/[(L1/2)i(n(i)) + I(n(i))], where the n(i)'s are the number of sites used by the incident photons in their interaction with the photosynthetic pigments in each population i of PSII centers open for photochemistry. The mathematical simulations yielded only three distinct n(i)'s, that is, 1.8, 4.8, 8.5 and 1.8, 4.2, 8.4 for isolated PSII particles incubated with DCBQ and pBQ, respectively. Implicitly, this means the simultaneous excitation of each PSII reaction center with more than one photon, that is, the excitation of more than one pigment molecule. It is suggested that these transitions have their origin in the cooperative interaction of the photons and the chlorophylls, and most likely also the pheophytins. This indicates that the discontinuities (or transitions) observed in the light-response curves of oxygen evolution are consistent with the hypothesis of photochemical cooperativity in photosystem II.
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Affiliation(s)
- V Viruvuru
- Département de Chimie-Biologie, Université du Québec à Trois-Rivières, Trois-Rivières, Québec, Canada G9A 5H7.
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Martínez-Junza V, Szczepaniak M, Braslavsky SE, Sander J, Nowaczyk M, Rögner M, Holzwarth AR. A photoprotection mechanism involving the D(2) branch in photosystem II cores with closed reaction centers. Photochem Photobiol Sci 2008; 7:1337-43. [PMID: 18958320 DOI: 10.1039/b809884k] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nanosecond transient absorption spectroscopy has been used to study reaction centre (RC) chlorophyll triplet quenching by carotenoid in intact photosystem II cores from T. elongatus with closed RCs. We found a triplet beta-carotene ((3)Car) signal (absorption difference maximum at 530 nm) that is sensitized by the RC chlorophyll (Chl) triplet with a formation time of ca. 190 ns, has a decay time of 7 micros and is formed with a quantum yield between 10 and 20%. The (3)Car signal is assigned to the beta-carotene on the D(2) branch of the RC. We thus propose a new photoprotection mechanism operative in closed RCs where-as a consequence of the negative charge on the quinone Q(A)-the triplet chlorophyll ((3)Chl) is formed by the radical pair (RP) mechanism on the normally inactive D(2) branch where it can be subsequently quenched by the D(2) beta-carotene. We suggest that the D(2) branch becomes active when the RCs are closed under high light fluence conditions. Under these conditions the D(2) branch plays a photoprotective role. This interpretation allows combining many seemingly inconsistent observations in the literature and reveals the so far missing RC triplet quenching mechanism in photosystem II. The newly proposed mechanism also explains the reason why this RC triplet quenching is not observed in isolated D(1)-D(2)-cyt b(559) RCs. If Q(A) is either not present at all (as in the isolated RC) or is not charged (as in open RCs or with doubly reduced Q(A)) then the RC (3)Chl is formed on the D(1) branch. The D(1) branch (3)Chl can not be quenched due to the large distance to the beta-carotene. This interpretation is actually in line with the well-known (3)RC quenching mechanism in bacterial RCs, where also the carotenoid in the (analogous to the D(2) branch) B-branch of the RC becomes the quencher.
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Badura A, Guschin D, Esper B, Kothe T, Neugebauer S, Schuhmann W, Rögner M. Photo-Induced Electron Transfer Between Photosystem 2 via Cross-linked Redox Hydrogels. ELECTROANAL 2008. [DOI: 10.1002/elan.200804191] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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40
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Suhai T, Dencher NA, Poetsch A, Seelert H. Remarkable stability of the proton translocating F1FO-ATP synthase from the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1778:1131-40. [PMID: 18206981 DOI: 10.1016/j.bbamem.2007.12.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2007] [Revised: 11/28/2007] [Accepted: 12/13/2007] [Indexed: 10/22/2022]
Abstract
For functional characterization, we isolated the F1FO-ATP synthase of the thermophilic cyanobacterium Thermosynechococcus elongatus. Because of the high content of phycobilisomes, a combination of dye-ligand chromatography and anion exchange chromatography was necessary to yield highly pure ATP synthase. All nine single F1FO subunits were identified by mass spectrometry. Western blotting revealed the SDS stable oligomer of subunits c in T. elongatus. In contrast to the mass archived in the database (10,141 Da), MALDI-TOF-MS revealed a mass of the subunit c monomer of only 8238 Da. A notable feature of the ATP synthase was its ability to synthesize ATP in a wide temperature range and its stability against chaotropic reagents. After reconstitution of F1FO into liposomes, ATP synthesis energized by an applied electrochemical proton gradient demonstrated functional integrity. The highest ATP synthesis rate was determined at the natural growth temperature of 55 degrees C, but even at 95 degrees C ATP production occurred. In contrast to other prokaryotic and eukaryotic ATP synthases which can be disassembled with Coomassie dye into the membrane integral and the hydrophilic part, the F1FO-ATP synthase possessed a particular stability. Also with the chaotropic reagents sodium bromide and guanidine thiocyanate, significantly harsher conditions were required for disassembly of the thermophilic ATP synthase.
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Affiliation(s)
- Tina Suhai
- Physical Biochemistry, Department of Chemistry, Darmstadt University of Technology, Petersenstrasse 22, D-64287 Darmstadt, Germany
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41
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Single particle analysis of thylakoid proteins from Thermosynechococcus elongatus and Synechocystis 6803: localization of the CupA subunit of NDH-1. FEBS Lett 2007; 582:249-54. [PMID: 18083126 DOI: 10.1016/j.febslet.2007.12.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Revised: 12/05/2007] [Accepted: 12/06/2007] [Indexed: 11/20/2022]
Abstract
The larger protein complexes of the cyanobacterial photosynthetic membrane of Thermosynechoccus elongatus and Synechocystis 6803 were studied by single particle electron microscopy after detergent solubilization, without any purification steps. Besides the "standard" L-shaped NDH-1L complex, related to complex I, large numbers of a U-shaped NDH-1MS complex were found in both cyanobacteria. In membranes from Synechocystis DeltacupA and DeltacupA/cupB mutants the U-shaped complexes were absent, indicating that CupA is responsible for the U-shape by binding at the tip of the membrane-bound arm of NDH-1MS. Comparison of membranes grown under air levels of CO(2) or 3% CO(2) indicates that the number of NDH-1MS particles is 30-fold higher under low-CO(2).
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42
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Ma L, Wang HY. Mitogen-activated protein kinase p38 regulates the Wnt/cyclic GMP/Ca2+ non-canonical pathway. J Biol Chem 2007; 282:28980-28990. [PMID: 17684012 DOI: 10.1074/jbc.m702840200] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The non-canonical Wnt/cyclic GMP/Ca(2+)/NF-AT pathway operates via Frizzled-2, a member of the superfamily of G protein-coupled receptors. In scanning for signaling events downstream of the Frizzled-2/G alpha t2/PDE6 triad activated in response to Wnt5a, we observed a strong activation of the mitogen-activated protein kinase p38 in mouse F9 teratocarcinoma embryonal cells. The activation of p38 is essential for NF-AT transcriptional activation mediated via Frizzled2. Wnt5a-stimulated p38 activation was rapid, sensitive to pertussis toxin, to siRNA against either G alpha t2 or p38 alpha, and to the p38 inhibitor SB203580. Real-time analysis of intracellular cyclic GMP using the Cygnet2 biosensor revealed p38 to act at the level of cyclic GMP, upstream of the mobilization of intracellular Ca(2+). Fluorescence resonance energy transfer (FRET) imaging reveals the changes in cyclic GMP in response to Wnt5a predominate about the cell membrane, and likewise sensitive to either siRNA targeting p38 or to treatment with SB203580. Dishevelled is not required for Wnt5a activation of p38; siRNAs targeting Dishevelleds and expression of the Dishevelled antagonist Dapper-1 do not suppress the p38 response to Wnt5a stimulation. These novel results are the first to detail a Dishevelled-independent Wnt response, demonstrating a critical role of the mitogen-activated protein kinase p38 in regulating the Wnt non-canonical pathway.
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Affiliation(s)
- Li Ma
- Departments of Physiology & Biophysics, Diabetes & Metabolic Diseases Research Center, School of Medicine, State University of New York/Stony Brook, Stony Brook, New York 11794-8661
| | - Hsien-Yu Wang
- Departments of Physiology & Biophysics, Diabetes & Metabolic Diseases Research Center, School of Medicine, State University of New York/Stony Brook, Stony Brook, New York 11794-8661.
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43
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Kern J, Biesiadka J, Loll B, Saenger W, Zouni A. Structure of the Mn4-Ca cluster as derived from X-ray diffraction. PHOTOSYNTHESIS RESEARCH 2007; 92:389-405. [PMID: 17492491 DOI: 10.1007/s11120-007-9173-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2006] [Accepted: 04/10/2007] [Indexed: 05/15/2023]
Abstract
The catalytic centre for light-induced water oxidation in photosystem II (PSII) is a multinuclear metal cluster containing four manganese and one calcium cations. Knowing the structure of this biological catalyst is of utmost importance for unravelling the mechanism of water oxidation in photosynthesis. In this review we describe the current state of the X-ray structure determination at 3.0 A resolution of the water oxidation complex (WOC) of PSII. The arrangement of metal cations in the cluster, their coordination and protein surroundings are discussed with regard to spectroscopic and mutagenesis studies. Limitations of the presently available structural data are pointed out and possible perspectives for the future are outlined, including the combination of X-ray diffraction and X-ray spectroscopy on single crystals.
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Affiliation(s)
- Jan Kern
- Institut für Chemie, Max Volmer Laboratorium für Biophysikalische Chemie, Sekr. PC 14, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany.
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44
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Lax JEM, Arteni AA, Boekema EJ, Pistorius EK, Michel KP, Rögner M. Structural response of Photosystem 2 to iron deficiency: Characterization of a new Photosystem 2–IdiA complex from the cyanobacterium Thermosynechococcus elongatus BP-1. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2007; 1767:528-34. [PMID: 17316552 DOI: 10.1016/j.bbabio.2007.01.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2006] [Revised: 12/12/2006] [Accepted: 01/04/2007] [Indexed: 11/17/2022]
Abstract
Iron deficiency triggers various processes in cyanobacterial cells of which the synthesis of an additional antenna system (IsiA) around photosystem (PS) 1 is well documented [T.S. Bibby, J. Nield, J. Barber, Iron deficiency induces the formation of an antenna ring around trimeric photosystem I in cyanobacteria, Nature 412 (2001) 743-745, E.J. Boekema, A. Hifney, A.E. Yakushevska, M. Piotrowski, W. Keegstra, S. Berry, K.P. Michel, E.K. Pistorius, J. Kruip, A giant chlorophyll-protein complex induced by iron deficiency in cyanobacteria, Nature 412 (2001) 745-748]. Here we show that PS2 also undergoes prominent structural changes upon iron deficiency: Prerequisite is the isolation and purification of a PS2-IdiA complex which is exclusively synthesized under these conditions. Immunoblotting in combination with size exclusion chromatography shows that IdiA is only bound to dimeric PS2. Using single particle analysis of negatively stained specimens, IdiA can be localized in averaged electron micrographs on top of the CP43 subunit facing the cytoplasmic side in a model derived from the known 3D structure of PS2 [B. Loll, J. Kern, W. Saenger, A. Zouni, J. Biesiadka, Towards complete cofactor arrangement in the 3.0 A resolution structure of photosystem II, Nature 438 (2005) 1040-4]. The presence of IdiA as integral part of PS2 is the first example of a new PS2 protein being expressed under stress conditions, which is missing in highly purified PS2 complexes isolated from iron-sufficient cells.
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Affiliation(s)
- Julia E-M Lax
- Plant Biochemistry, Faculty of Biology, Ruhr-University Bochum, 44780 Bochum, Germany
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Fragata M, Viruvuru V, Dudekula S. Theoretical consideration of the use of a Langmuir adsorption isotherm to describe the effect of light intensity on electron transfer in photosystem II. J Phys Chem B 2007; 111:3315-20. [PMID: 17388444 DOI: 10.1021/jp0684271] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Electron transport through photosystem II (PSII), measured as oxygen evolution, was investigated in isolated PSII particles and thylakoid membranes irradiated with white light of intensities (I) of 20 to about 4000 micromol of photons/(m2.s). In steady-state conditions, the evolution of oxygen varies with I according to the hyperbolic expression OEth = OEth(max)I/(L1/2 + I) (eq i) where OEth is the theoretical oxygen evolution, OEth(max) is the maximum oxygen evolution, and L1/2 is the light intensity giving OEth(max)/2. In this work, the mathematical derivation of this relationship was performed by using the Langmuir adsorption isotherm and assuming that the photon interaction with the chlorophyll (Chl) in the PSII reaction center is a heterogeneous reaction in which the light is represented as a stream of particles instead of an electromagnetic wave (see discussion in Turro, N. J. Modern Molecular Photochemistry; University Science Books: Mill Valley, CA, 1991). In accordance with this approximation, the Chl molecules (P680) were taken as the adsorption surfaces (or heterogeneous catalysts), and the incident (or exciting) photons as the substrate, or the reagent. Using these notions, we demonstrated that eq i (Langmuir equation) is a reliable interpretation of the photon-P680 interaction and the subsequent electron transfer from the excited state P680, i.e., P680*, to the oxidized pheophytin (Phe), then from Phe- to the primary quinone QA. First, eq i contains specific functional and structural information that is apparent in the definition of OEth(max) as a measure of the maximal number of PSII reaction centers open for photochemistry, and L1/2 as the equilibrium between the electron transfer from Phe- to QA and the formation of reduced Phe in the PSII reaction center by electrons in provenance from P680*. Second, a physiological control mechanism in eq i is proved by the observation that the magnitudes of OEth(max) and L1/2 are affected differently by exogenous PSII stimulators of oxygen evolution (Fragata, M.; Dudekula, S. J. Phys. Chem. B 2005, 109, 14707). Finally, an unexpected new concept, implicit in eq i, is the consideration of the photon as the substrate in the photochemical reactions taking place in the PSII reaction center. We conclude that the Langmuir equation (eq i) is a novel mathematical formulation of energy and electron transfer in photosystem II.
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Affiliation(s)
- Mário Fragata
- Université du Québec à Trois-Rivières, Département de Chimie-Biologie, Section de Chimie et Biochimie, Trois-Rivières, Québec, G9A 5H7, Canada.
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Kargul J, Maghlaoui K, Murray JW, Deak Z, Boussac A, Rutherford AW, Vass I, Barber J. Purification, crystallization and X-ray diffraction analyses of the T. elongatus PSII core dimer with strontium replacing calcium in the oxygen-evolving complex. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2007; 1767:404-13. [PMID: 17321490 DOI: 10.1016/j.bbabio.2007.01.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2006] [Revised: 01/05/2007] [Accepted: 01/09/2007] [Indexed: 11/17/2022]
Abstract
The core complex of photosystem II (PSII) was purified from thermophilic cyanobacterium Thermosynechococcus elongatus grown in Sr(2+)-containing and Ca(2+)-free medium. Functional in vivo incorporation of Sr(2+) into the oxygen-evolving complex (OEC) was confirmed by EPR analysis of the isolated and highly purified SrPSII complex in agreement with the previous study of Boussac et al. [J. Biol. Chem. 279 (2004) 22809-22819]. Three-dimensional crystals of SrPSII complex were obtained which diffracted to 3.9 A and belonged to the orthorhombic space group P2(1)2(1)2(1) with unit cell dimensions of a=133.6 A, b=236.6 A, c=307.8 A. Anomalous diffraction data collected at the Sr K-X-ray absorption edge identified a novel Sr(2+)-binding site which, within the resolution of these data (6.5 A), is consistent with the positioning of Ca(2+) in the recent crystallographic models of PSII [Ferreira et al. Science 303 (2004) 1831-1838, Loll et al. Nature 438 (2005) 1040-1044]. Fluorescence measurements on SrPSII crystals confirmed that crystallized SrPSII was active in transferring electrons from the OEC to the acceptor site of the reaction centre. However, SrPSII showed altered functional properties of its modified OEC in comparison with that of the CaPSII counterpart: slowdown of the Q(A)-to-Q(B) electron transfer and stabilized S(2)Q(A)(-) charge recombination.
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Affiliation(s)
- Joanna Kargul
- Wolfson Laboratories, Division of Molecular Biosciences, Faculty of Natural Sciences, Imperial College London, London, UK
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Kutá Smatanová I, Gavira JA, Rezácová P, Vácha F, García-Ruiz JM. New techniques for membrane protein crystallization tested on photosystem II core complex of Pisum sativum. PHOTOSYNTHESIS RESEARCH 2006; 90:255-9. [PMID: 17279440 DOI: 10.1007/s11120-007-9131-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2006] [Accepted: 01/04/2007] [Indexed: 05/13/2023]
Abstract
The crystallization of a given protein is a hard task being even more complicated when the protein shows a hydrophobic behavior. In the case of photosynthetic proteins, the difficulty of the experiments increased due to the high light sensitivity. Aqueous solutions of photosystem II core complex (OEC PSII) of Pisum sativum were screened for crystallization conditions using standard crystallization methods. Crystal improvement was achieved by counter-diffusion technique in single capillaries of 0.2 mm inner diameter with a three-layer configuration. The use of this advanced crystallization technique-for the first time applied to the crystallization of membrane proteins-improves the reproducibility of the experiments allowing the initial crystal characterization, and facilitates the manipulation under light protection.
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Affiliation(s)
- Ivana Kutá Smatanová
- Institute of Physical Biology, University of South Bohemia Ceske Budejovice, Zamek 136, 373 33, Nove Hrady, Czech Republic.
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Dudekula S, Fragata M. Investigation of the electron transfer site of p-benzoquinone in isolated photosystem II particles and thylakoid membranes using α- and β-cyclodextrins. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2006; 85:177-83. [PMID: 16934484 DOI: 10.1016/j.jphotobiol.2006.07.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Revised: 07/02/2006] [Accepted: 07/19/2006] [Indexed: 11/22/2022]
Abstract
The electron transfer sites of p-benzoquinone (pBQ) and 2,6-dichloro-p-benzoquinone (DCBQ) were investigated in thylakoid membranes and isolated photosystem II (PSII) particles from barley (Hordeum vulgare) using alpha- and beta-cyclodextrins (CD) at concentrations up to 16 mM. In CD-treated thylakoid membranes incubated with DCBQ the electron transport through PSII, estimated as oxygen evolution (OE), is largely enhanced according to a S-shaped (sigmoidal) dose-response curve displaying a sharp inflection point, or transition. The maxima percent OE enhancement at cyclodextrin concentrations above 14 mM are about 100% (alpha-CD) and 190% (beta-CD). On the contrary, in thylakoid membrane preparations incubated with pBQ as electron acceptor one observes an OE inhibition of about 30% which might result from the depletion of the thylakoid membrane of its plastoquinone content. It was also found that in isolated PSII particles incubated with either pBQ or DCBQ the cyclodextrins induce only a small OE enhancement. Moreover, the observation in CD-treated thylakoid membranes incubated with pBQ of a residual, non-inhibited oxygen-evolving activity of about 70% puts a twofold question. That is, either the plastoquinone depletion was not complete, or, pBQ binds to electron acceptor sites of different nature. From this and data published in the literature, it is concluded that in the thylakoid membrane (i) DCBQ binds to Q(B), as is generally accepted, and (ii) pBQ binds to the plastoquinol molecules in the PQ pool and most likely also to Q(B), thereby in accord with Satoh et al.'s model [K. Satoh, M. Ohhashi, Y. Kashino, H. Koike, Plant Cell Physiol. 36 (1995) 597-605]. An attractive alternative hypothesis is the direct interaction of pBQ with the non-haem Fe(2+) between Q(A) and Q(B).
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Affiliation(s)
- S Dudekula
- Center for Cellular and Molecular Biology, Habsiguda, Hyderabad 500007, Andhrapradesh, India
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Holzwarth AR, Müller MG, Reus M, Nowaczyk M, Sander J, Rögner M. Kinetics and mechanism of electron transfer in intact photosystem II and in the isolated reaction center: pheophytin is the primary electron acceptor. Proc Natl Acad Sci U S A 2006; 103:6895-900. [PMID: 16641109 PMCID: PMC1458990 DOI: 10.1073/pnas.0505371103] [Citation(s) in RCA: 231] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The mechanism and kinetics of electron transfer in isolated D1/D2-cyt(b559) photosystem (PS) II reaction centers (RCs) and in intact PSII cores have been studied by femtosecond transient absorption and kinetic compartment modeling. For intact PSII, a component of approximately 1.5 ps reflects the dominant energy-trapping kinetics from the antenna by the RC. A 5.5-ps component reflects the apparent lifetime of primary charge separation, which is faster by a factor of 8-12 than assumed so far. The 35-ps component represents the apparent lifetime of formation of a secondary radical pair, and the approximately 200-ps component represents the electron transfer to the Q(A) acceptor. In isolated RCs, the apparent lifetimes of primary and secondary charge separation are approximately 3 and 11 ps, respectively. It is shown (i) that pheophytin is reduced in the first step, and (ii) that the rate constants of electron transfer in the RC are identical for PSII cores and for isolated RCs. We interpret the first electron transfer step as electron donation from the primary electron donor Chl(acc D1). Thus, this mechanism, suggested earlier for isolated RCs at cryogenic temperatures, is also operative in intact PSII cores and in isolated RCs at ambient temperature. The effective rate constant of primary electron transfer from the equilibrated RC* excited state is 170-180 ns(-1), and the rate constant of secondary electron transfer is 120-130 ns(-1).
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Affiliation(s)
- A R Holzwarth
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim a.d. Ruhr, Germany.
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Iwai M, Katayama M, Ikeuchi M. Absence of the psbH gene product destabilizes the Photosystem II complex and prevents association of the Photosystem II-X protein in the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1. PHOTOSYNTHESIS RESEARCH 2006; 87:313-22. [PMID: 16699922 DOI: 10.1007/s11120-005-9013-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2005] [Accepted: 08/08/2005] [Indexed: 05/09/2023]
Abstract
PS II-H is a small hydrophobic protein that is universally present in the PS II core complex of cyanobacteria and plants. The role of PS II-H was studied by directed mutagenesis and biochemical analysis in the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1. The psbH disruptant could grow photoautotrophically; however, its growth was much slower than that of the wild type cell. Chromatography enabled the isolation of active oxygen-evolving PS II complexes from both the mutant and the wild type. The mutant yielded a relatively large amount of inactive PS II complex that lacked the following extrinsic proteins: the 33-kDa protein, the 12-kDa protein, and cytochrome c ( 550 ). There were differences between the psbH disruptant and the wild type in terms of the oxygen evolution activities of the cells, thylakoids, and PS II complexes. At high concentrations of 2,6-DCBQ, the activity was much lower in the mutant than in the wild type. Gel filtration chromatography of the PS II complexes showed that both active and inactive PS II complexes isolated from the mutant were mostly in the monomeric form, while the active PS II complex from the wild type was in the dimeric form. The polypeptide composition of both active and inactive PS II complexes from the mutant showed the absence of another small polypeptide, PS II-X. These results suggest that the PS II-H protein is essential for stable assembly of native dimeric PS II complex containing PS II-X.
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Affiliation(s)
- Masako Iwai
- Department of Life Sciences (Biology), University of Tokyo, Komaba 3-8-1, Meguro, Tokyo, 153-8902, Japan.
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