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Bindra JK, Malavath T, Teferi MY, Kretzschmar M, Kern J, Niklas J, Utschig LM, Poluektov OG. Light-Induced Charge Separation in Photosystem I from Different Biological Species Characterized by Multifrequency Electron Paramagnetic Resonance Spectroscopy. Int J Mol Sci 2024; 25:8188. [PMID: 39125759 PMCID: PMC11311511 DOI: 10.3390/ijms25158188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2024] [Revised: 07/15/2024] [Accepted: 07/19/2024] [Indexed: 08/12/2024] Open
Abstract
Photosystem I (PSI) serves as a model system for studying fundamental processes such as electron transfer (ET) and energy conversion, which are not only central to photosynthesis but also have broader implications for bioenergy production and biomimetic device design. In this study, we employed electron paramagnetic resonance (EPR) spectroscopy to investigate key light-induced charge separation steps in PSI isolated from several green algal and cyanobacterial species. Following photoexcitation, rapid sequential ET occurs through either of two quasi-symmetric branches of donor/acceptor cofactors embedded within the protein core, termed the A and B branches. Using high-frequency (130 GHz) time-resolved EPR (TR-EPR) and deuteration techniques to enhance spectral resolution, we observed that at low temperatures prokaryotic PSI exhibits reversible ET in the A branch and irreversible ET in the B branch, while PSI from eukaryotic counterparts displays either reversible ET in both branches or exclusively in the B branch. Furthermore, we observed a notable correlation between low-temperature charge separation to the terminal [4Fe-4S] clusters of PSI, termed FA and FB, as reflected in the measured FA/FB ratio. These findings enhance our understanding of the mechanistic diversity of PSI's ET across different species and underscore the importance of experimental design in resolving these differences. Though further research is necessary to elucidate the underlying mechanisms and the evolutionary significance of these variations in PSI charge separation, this study sets the stage for future investigations into the complex interplay between protein structure, ET pathways, and the environmental adaptations of photosynthetic organisms.
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Affiliation(s)
- Jasleen K. Bindra
- Argonne National Laboratory, Chemical Sciences and Engineering Division, 9700 South Cass Avenue, Lemont, IL 60439, USA; (J.K.B.); (T.M.); (M.Y.T.); (J.N.)
| | - Tirupathi Malavath
- Argonne National Laboratory, Chemical Sciences and Engineering Division, 9700 South Cass Avenue, Lemont, IL 60439, USA; (J.K.B.); (T.M.); (M.Y.T.); (J.N.)
| | - Mandefro Y. Teferi
- Argonne National Laboratory, Chemical Sciences and Engineering Division, 9700 South Cass Avenue, Lemont, IL 60439, USA; (J.K.B.); (T.M.); (M.Y.T.); (J.N.)
| | - Moritz Kretzschmar
- Lawrence Berkeley National Laboratory, Molecular Biophysics and Integrated Bioimaging Division, Berkeley, CA 94720, USA; (M.K.); (J.K.)
| | - Jan Kern
- Lawrence Berkeley National Laboratory, Molecular Biophysics and Integrated Bioimaging Division, Berkeley, CA 94720, USA; (M.K.); (J.K.)
| | - Jens Niklas
- Argonne National Laboratory, Chemical Sciences and Engineering Division, 9700 South Cass Avenue, Lemont, IL 60439, USA; (J.K.B.); (T.M.); (M.Y.T.); (J.N.)
| | - Lisa M. Utschig
- Argonne National Laboratory, Chemical Sciences and Engineering Division, 9700 South Cass Avenue, Lemont, IL 60439, USA; (J.K.B.); (T.M.); (M.Y.T.); (J.N.)
| | - Oleg G. Poluektov
- Argonne National Laboratory, Chemical Sciences and Engineering Division, 9700 South Cass Avenue, Lemont, IL 60439, USA; (J.K.B.); (T.M.); (M.Y.T.); (J.N.)
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Santabarbara S, Agostini A, Petrova AA, Bortolus M, Casazza AP, Carbonera D. Chlorophyll triplet states in thylakoid membranes of Acaryochloris marina. Evidence for a triplet state sitting on the photosystem I primary donor populated by intersystem crossing. PHOTOSYNTHESIS RESEARCH 2024; 159:133-152. [PMID: 37191762 DOI: 10.1007/s11120-023-01023-z] [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: 03/16/2023] [Accepted: 04/27/2023] [Indexed: 05/17/2023]
Abstract
Photo-induced triplet states in the thylakoid membranes isolated from the cyanobacterium Acaryocholoris marina, that harbours Chlorophyll (Chl) d as its main chromophore, have been investigated by Optically Detected Magnetic Resonance (ODMR) and time-resolved Electron Paramagnetic Resonance (TR-EPR). Thylakoids were subjected to treatments aimed at poising the redox state of the terminal electron transfer acceptors and donors of Photosystem II (PSII) and Photosystem I (PSI), respectively. Under ambient redox conditions, four Chl d triplet populations were detectable, identifiable by their characteristic zero field splitting parameters, after deconvolution of the Fluorescence Detected Magnetic Resonance (FDMR) spectra. Illumination in the presence of the redox mediator N,N,N',N'-Tetramethyl-p-phenylenediamine (TMPD) and sodium ascorbate at room temperature led to a redistribution of the triplet populations, with T3 (|D|= 0.0245 cm-1, |E|= 0.0042 cm-1) becoming dominant and increasing in intensity with respect to untreated samples. A second triplet population (T4, |D|= 0.0248 cm-1, |E|= 0.0040 cm-1) having an intensity ratio of about 1:4 with respect to T3 was also detectable after illumination in the presence of TMPD and ascorbate. The microwave-induced Triplet-minus-Singlet spectrum acquired at the maximum of the |D|-|E| transition (610 MHz) displays a broad minimum at 740 nm, accompanied by a set of complex spectral features that overall resemble, despite showing further fine spectral structure, the previously reported Triplet-minus-Singlet spectrum attributed to the recombination triplet of PSI reaction centre,3 P 740 [Schenderlein M, Çetin M, Barber J, et al. Spectroscopic studies of the chlorophyll d containing photosystem I from the cyanobacterium Acaryochloris marina. Biochim Biophys Acta 1777:1400-1408]. However, TR-EPR experiments indicate that this triplet displays an eaeaea electron spin polarisation pattern which is characteristic of triplet sublevels populated by intersystem crossing rather than recombination, for which an aeeaae polarisation pattern is expected instead. It is proposed that the observed triplet, which leads to the bleaching of the P740 singlet state, sits on the PSI reaction centre.
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Affiliation(s)
- Stefano Santabarbara
- Photosynthesis Research Unit, Centro Studi Sulla Biologia Cellulare e Molecolare delle Piante, Consiglio Nazionale Delle Ricerche, Via Celoria 26, 20133, Milan, Italy.
- Istituto di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche, Via Bassini 15a, 20133, Milan, Italy.
| | - Alessandro Agostini
- Department of Chemical Sciences, Università di Padova, Via Marzolo 1, 35131, Padua, Italy
| | - Anastasia A Petrova
- Photosynthesis Research Unit, Centro Studi Sulla Biologia Cellulare e Molecolare delle Piante, Consiglio Nazionale Delle Ricerche, Via Celoria 26, 20133, Milan, Italy
- A. N. Belozersky Institute of Physical-Chemical Biology, Lomonosov Moscow State University, Leninskye Gory 1 Building 40, Moscow, Russia, 119992
| | - Marco Bortolus
- Department of Chemical Sciences, Università di Padova, Via Marzolo 1, 35131, Padua, Italy
| | - Anna Paola Casazza
- Istituto di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche, Via Bassini 15a, 20133, Milan, Italy
| | - Donatella Carbonera
- Department of Chemical Sciences, Università di Padova, Via Marzolo 1, 35131, Padua, Italy.
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3
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Zheng JW, He GH, Xu RX, Wang X, Li HY, Yang WD. Systematic exploration of transcriptional responses of interspecies interaction between Karenia mikimotoi and Prorocentrum shikokuense. HARMFUL ALGAE 2023; 126:102441. [PMID: 37290889 DOI: 10.1016/j.hal.2023.102441] [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: 11/10/2022] [Revised: 04/27/2023] [Accepted: 04/29/2023] [Indexed: 06/10/2023]
Abstract
Karenia mikimotoi and Prorocentrum shikokuense (also identified as P. donghaiense Lu and P. obtusidens Schiller) are two important harmful algal species which often form blooms in the coasts of China. Studies have shown that the allelopathy of K. mikimotoi and P. shikokuense plays an important role in inter-algal competition, though the underlying mechanisms remain largely unclear. Here, we observed reciprocal inhibitory effects between K. mikimotoi and P. shikokuense under co-cultures. Based on the reference sequences, we isolated RNA sequencing reads of K. mikimotoi and P. shikokuense from co-culture metatranscriptome, respectively. We found the genes involved in photosynthesis, carbon fixation, energy metabolism, nutrients absorption and assimilation were significantly up-regulated in K. mikimotoi after co-cultured with P. shikokuense. However, genes involved in DNA replication and cell cycle were significantly down-regulated. These results suggested that co-culture with P. shikokuense stimulated cell metabolism and nutrients competition activity of K. mikimotoi, and inhibited cell cycle. In contrast, genes involved in energy metabolism, cell cycle and nutrients uptake and assimilation were dramatically down-regulated in P. shikokuense under co-culture with K. mikimotoi, indicating that K. mikimotoi could highly affect the cellular activity of P. shikokuense. In addition, the expression of PLA2G12 (Group XII secretory phospholipase A2) that can catalyze the accumulation of linoleic acid or linolenic acid, and nitrate reductase that may be involved in nitric oxide production were significantly increased in K. mikimotoi, suggesting that PLA2G12 and nitrate reductase may play important roles in the allelopathy of K. mikimotoi. Our findings shed new light on the interspecies competition between K. mikimotoi and P. shikokuense, and provide a novel strategy for studying interspecific competition in complex systems.
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Affiliation(s)
- Jian-Wei Zheng
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China; College of Food Science and Engineering, Foshan University of Science and Technology, Foshan 528231, China
| | - Guo-Hui He
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Rui-Xia Xu
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Xiang Wang
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Hong-Ye Li
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China
| | - Wei-Dong Yang
- Key Laboratory of Aquatic Eutrophication and Control of Harmful Algal Blooms of Guangdong Higher Education Institute, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
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Reiter S, Kiss FL, Hauer J, de Vivie-Riedle R. Thermal site energy fluctuations in photosystem I: new insights from MD/QM/MM calculations. Chem Sci 2023; 14:3117-3131. [PMID: 36970098 PMCID: PMC10034153 DOI: 10.1039/d2sc06160k] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 02/03/2023] [Indexed: 02/09/2023] Open
Abstract
Cyanobacterial photosystem I (PSI) is one of the most efficient photosynthetic machineries found in nature. Due to the large scale and complexity of the system, the energy transfer mechanism from the antenna complex to the reaction center is still not fully understood. A central element is the accurate evaluation of the individual chlorophyll excitation energies (site energies). Such an evaluation must include a detailed treatment of site specific environmental influences on structural and electrostatic properties, but also their evolution in the temporal domain, because of the dynamic nature of the energy transfer process. In this work, we calculate the site energies of all 96 chlorophylls in a membrane-embedded model of PSI. The employed hybrid QM/MM approach using the multireference DFT/MRCI method in the QM region allows to obtain accurate site energies under explicit consideration of the natural environment. We identify energy traps and barriers in the antenna complex and discuss their implications for energy transfer to the reaction center. Going beyond previous studies, our model also accounts for the molecular dynamics of the full trimeric PSI complex. Via statistical analysis we show that the thermal fluctuations of single chlorophylls prevent the formation of a single prominent energy funnel within the antenna complex. These findings are also supported by a dipole exciton model. We conclude that energy transfer pathways may form only transiently at physiological temperatures, as thermal fluctuations overcome energy barriers. The set of site energies provided in this work sets the stage for theoretical and experimental studies on the highly efficient energy transfer mechanisms in PSI.
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Affiliation(s)
- Sebastian Reiter
- Department of Chemistry, Ludwig-Maximilians-Universität München Butenandtstr. 11 81377 Munich Germany
| | - Ferdinand L Kiss
- Department of Chemistry, Ludwig-Maximilians-Universität München Butenandtstr. 11 81377 Munich Germany
| | - Jürgen Hauer
- Department of Chemistry, Technical University of Munich Lichtenbergstr. 4, Garching 85747 Germany
| | - Regina de Vivie-Riedle
- Department of Chemistry, Ludwig-Maximilians-Universität München Butenandtstr. 11 81377 Munich Germany
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5
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Zhang S, Zou B, Cao P, Su X, Xie F, Pan X, Li M. Structural insights into photosynthetic cyclic electron transport. MOLECULAR PLANT 2023; 16:187-205. [PMID: 36540023 DOI: 10.1016/j.molp.2022.12.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/17/2022] [Accepted: 12/18/2022] [Indexed: 06/17/2023]
Abstract
During photosynthesis, light energy is utilized to drive sophisticated biochemical chains of electron transfers, converting solar energy into chemical energy that feeds most life on earth. Cyclic electron transfer/flow (CET/CEF) plays an essential role in efficient photosynthesis, as it balances the ATP/NADPH ratio required in various regulatory and metabolic pathways. Photosystem I, cytochrome b6f, and NADH dehydrogenase (NDH) are large multisubunit protein complexes embedded in the thylakoid membrane of the chloroplast and key players in NDH-dependent CEF pathway. Furthermore, small mobile electron carriers serve as shuttles for electrons between these membrane protein complexes. Efficient electron transfer requires transient interactions between these electron donors and acceptors. Structural biology has been a powerful tool to advance our knowledge of this important biological process. A number of structures of the membrane-embedded complexes, soluble electron carrier proteins, and transient complexes composed of both have now been determined. These structural data reveal detailed interacting patterns of these electron donor-acceptor pairs, thus allowing us to visualize the different parts of the electron transfer process. This review summarizes the current state of structural knowledge of three membrane complexes and their interaction patterns with mobile electron carrier proteins.
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Affiliation(s)
- Shumeng Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Baohua Zou
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Peng Cao
- Faculty of Environment and Life, Beijing University of Technology, Beijing, China
| | - Xiaodong Su
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Fen Xie
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Xiaowei Pan
- College of Life Science, Capital Normal University, Beijing, China
| | - Mei Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
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Russo M, Casazza AP, Cerullo G, Santabarbara S, Maiuri M. Ultrafast excited state dynamics in the monomeric and trimeric photosystem I core complex of Spirulina platensis probed by two-dimensional electronic spectroscopy. J Chem Phys 2022; 156:164202. [PMID: 35490013 DOI: 10.1063/5.0078911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Photosystem I (PSI), a naturally occurring supercomplex composed of a core part and a light-harvesting antenna, plays an essential role in the photosynthetic electron transfer chain. Evolutionary adaptation dictates a large variability in the type, number, arrangement, and absorption of the Chlorophylls (Chls) responsible for the early steps of light-harvesting and charge separation. For example, the specific location of long-wavelength Chls (referred to as red forms) in the cyanobacterial core has been intensively investigated, but the assignment of the chromophores involved is still controversial. The most red-shifted Chl a form has been observed in the trimer of the PSI core of the cyanobacterium Spirulina platensis, with an absorption centered at ∼740 nm. Here, we apply two-dimensional electronic spectroscopy to study photoexcitation dynamics in isolated trimers and monomers of the PSI core of S. platensis. By means of global analysis, we resolve and compare direct downhill and uphill excitation energy transfer (EET) processes between the bulk Chls and the red forms, observing significant differences between the monomer (lacking the most far red Chl form at 740 nm) and the trimer, with the ultrafast EET component accelerated by five times, from 500 to 100 fs, in the latter. Our findings highlight the complexity of EET dynamics occurring over a broad range of time constants and their sensitivity to energy distribution and arrangement of the cofactors involved. The comparison of monomeric and trimeric forms, differing both in the antenna dimension and in the extent of red forms, enables us to extract significant information regarding PSI functionality.
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Affiliation(s)
- Mattia Russo
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Anna Paola Casazza
- Istituto di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche, Via Bassini 15a, 20133 Milano, Italy
| | - Giulio Cerullo
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Stefano Santabarbara
- Photosynthesis Research Unit, Centro Studi sulla Biologia Cellulare e Molecolare delle Piante, Consiglio Nazionale delle Ricerche, Via Celoria 26, 20133 Milano, Italy
| | - Margherita Maiuri
- Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
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Assessment of the orientation and conformation of pigments in protein binding sites from infrared difference spectra. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1862:148366. [PMID: 33385342 DOI: 10.1016/j.bbabio.2020.148366] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 12/16/2020] [Accepted: 12/19/2020] [Indexed: 01/01/2023]
Abstract
Time resolved FTIR difference spectroscopy (DS) has been used to study photosystem I (PSI) with the disubstituted 1,4-naphthoquinones acequinocyl (AcQ) and lapachol (Lpc) incorporated into the A1 binding site. AcQ is a 2-acetoxy-3-dodecyl-1,4-naphthoquinone, Lpc is a 2-hydroxy-3-(3-methyl-2-butenyl)-1,4-naphthoquinone. To assess whether the experimental spectra are specific to different orientations of the quinone and their substitutions ONIOM-type QM/MM vibrational frequency calculations were undertaken for various orientations of the pigments and side-chain conformations in the A1 binding site. Comparison of calculated and experimental spectra for the reduced species (semiquinone anion) suggests that the orientation for the naphthoquinone ring in the binding site and specific side-chain conformations can be identified based on the spectra. In native PSI phylloquinone (PhQ) in the A1 binding site binds with its phytyl chain ortho to the hydrogen bonded carbonyl group. This is not found to be the case for the hydrocarbon tail of AcQ, which is meta to the H-bonded carbonyl group. In contrast, Lpc in PSI binds with its hydrocarbon tail also ortho to the H-bonded carbonyl group. Furthermore, comparison of calculated and experimental spectra indicates which conformations the acetoxy group of AcQ and the hydroxy group of Lpc adopt in the A1 binding site.
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Santabarbara S, Casazza AP. Kinetics and Energetics of Phylloquinone Reduction in Photosystem I: Insight From Modeling of the Site Directed Mutants. FRONTIERS IN PLANT SCIENCE 2019; 10:852. [PMID: 31312208 PMCID: PMC6614487 DOI: 10.3389/fpls.2019.00852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 06/13/2019] [Indexed: 06/10/2023]
Abstract
Two phylloquinone molecules (A 1), one being predominantly coordinated by PsaA subunit residues (A 1A) the other by those of PsaB (A 1B), act as intermediates in the two parallel electron transfer chains of Photosystem I. The oxidation kinetics of the two phyllosemiquinones by the iron-sulfur cluster FX differ by approximately one order of magnitude, with A 1 A - being oxidized in about 200 ns and A 1 B - in about 20 ns. These differences are generally explained in terms of asymmetries in the driving force for FX reduction on the two electron transfer chains. Site directed mutations of conserved amino acids composing the A 1 binding site have been engineered on both reaction center subunits, and proved to affect selectively the oxidation lifetime of either A 1 A - , for PsaA mutants, or A 1 B - , for PsaB mutants. The mutation effects are here critically reviewed, also by novel modeling simulations employing the tunneling formalism to estimate the electron transfer rates. Three main classes of mutation effects are in particular addressed: (i) those leading to an acceleration, (ii) those leading to a moderated slowing (~5-folds), and (iii) those leading to a severe slowing (>20-folds) of the kinetics. The effect of specific amino acid perturbations contributing to the poising of the phylloquinones redox potential and, in turn, to PSI functionality, is discussed.
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Affiliation(s)
- Stefano Santabarbara
- Centre for Fundamental Research in Photosynthesis, Vergiate, Italy
- Photosynthesis Research Unit, Centro Studi sulla Biologia Cellulare e Molecolare delle Piante, Milan, Italy
| | - Anna Paola Casazza
- Istituto di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche, Milan, Italy
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9
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Santabarbara S, Casazza AP, Hastings G. Modelling electron transfer in photosystem I: limits and perspectives. PHYSIOLOGIA PLANTARUM 2019; 166:73-87. [PMID: 30847929 DOI: 10.1111/ppl.12959] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 03/05/2019] [Accepted: 03/05/2019] [Indexed: 06/09/2023]
Abstract
Uncovering the parameters underlying the electron transfer (ET) in photosynthetic reaction centres is of importance for understanding the molecular mechanisms underpinning their functionality. The reductive nature of most cofactors involved in photosynthetic ET makes the direct estimation of their properties difficult. Photosystem I (PSI) operates in a highly reducing regime, making the assessment of cofactor properties even more difficult. Kinetic modelling coupled to a non-adiabatic description of ET is a useful approach in overcoming this hindrance. Here we review the theory and modelling approaches that have been used in assessing parameters associated with ET reactions in PSI, with particular attention to ET reactions involving the phylloquinones and the iron-sulphur clusters. In most modelling studies, the goal is to estimate the driving force of ET, which is usually associated with the cofactor midpoint potentials. The driving force is sensitive to many factors, which define the ET rate, i.e. the reorganisation energy, the coupling with nuclear modes and the electronic matrix elements, which are explored and discussed here. The importance of an inclusive modelling of both forward and reverse ET processes is discussed and highlighted. It is shown that although estimates are indeed sensitive to the exact parameter sets employed in the modelling, a general consensus is still attained, pointing to a scenario where Δ G A 1 A → F X 0 / Δ G A 1 B → F X 0 is weakly endergonic/exergonic, respectively. It is emphasised that to further refine those estimates, it will require a joint effort between computational modelling and more wide-ranging experimental studies.
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Affiliation(s)
- Stefano Santabarbara
- Centre for Fundamental Research in Photosynthesis, 21029, Varese, Italy
- Photosynthesis Research Unit, Centro Studi sulla Biologia Cellulare e Molecolare delle Piante, 20133, Milan, Italy
| | - Anna Paola Casazza
- Istituto di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche, 20133, Milan, Italy
| | - Gary Hastings
- Department of Physics and Astronomy, Georgia State University, Atlanta, GA, 30303, USA
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Gao J, Wang H, Yuan Q, Feng Y. Structure and Function of the Photosystem Supercomplexes. FRONTIERS IN PLANT SCIENCE 2018; 9:357. [PMID: 29616068 PMCID: PMC5869908 DOI: 10.3389/fpls.2018.00357] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 03/02/2018] [Indexed: 05/21/2023]
Abstract
Photosynthesis converts solar energy into chemical energy to sustain all life on earth by providing oxygen and food, and controlling the atmospheric carbon dioxide. During this process, the water-splitting and oxygen-evolving reaction is catalyzed by photosystem II (PSII), while photosystem I (PSI) generates the reducing power for the reduction of NADP+ to NADPH. Together with their peripheral light-harvesting complexes (LHCs), photosystems function as multisubunit supercomplexes located in the thylakoid membranes of cyanobacteria, algae, and plants. Recent advances in single-particle cryo-electron microscopy (cryoEM), X-ray free electron laser (XFEL) and other techniques have revealed unprecedented structural and catalytic details concerning the two supercomplexes. Several high-resolution structures of the complexes from plants were solved, and serial time-resolved crystallography and "radiation-damage-free" femtosecond XFEL also provided important insights into the mechanism of water oxidation. Here, we review these exciting advances in the studies of the photosystem supercomplexes with an emphasis on PSII-LHCII, propose presently unresolved problems in this field, and suggest potential tendencies for future studies.
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Affiliation(s)
- Jinlan Gao
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Hao Wang
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Qipeng Yuan
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
| | - Yue Feng
- College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China
- *Correspondence: Yue Feng, ;
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11
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Mutations in algal and cyanobacterial Photosystem I that independently affect the yield of initial charge separation in the two electron transfer cofactor branches. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:42-55. [DOI: 10.1016/j.bbabio.2017.10.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 10/16/2017] [Accepted: 10/17/2017] [Indexed: 01/02/2023]
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12
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Molotokaite E, Remelli W, Casazza AP, Zucchelli G, Polli D, Cerullo G, Santabarbara S. Trapping Dynamics in Photosystem I-Light Harvesting Complex I of Higher Plants Is Governed by the Competition Between Excited State Diffusion from Low Energy States and Photochemical Charge Separation. J Phys Chem B 2017; 121:9816-9830. [DOI: 10.1021/acs.jpcb.7b07064] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Egle Molotokaite
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
| | - William Remelli
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
| | - Anna Paola Casazza
- Istituto
di Biologia e Biotecnologia Agraria, Consiglio Nazionale delle Ricerche, Via Bassini 15a, 20133 Milano, Italy
| | - Giuseppe Zucchelli
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
| | - Dario Polli
- Istituto di Fotonica e Nanotecnologie del CNR, Dipartimento di Fisica, Politecnico di Milano, P.zza Leonardo
da Vinci 32, 20133 Milano, Italy
- Center
for Nano Science and Technology at Polimi, Istituto Italiano di Tecnologia, Via Giovanni Pascoli, 70/3, 20133 Milano, Italy
| | - Giulio Cerullo
- Istituto di Fotonica e Nanotecnologie del CNR, Dipartimento di Fisica, Politecnico di Milano, P.zza Leonardo
da Vinci 32, 20133 Milano, Italy
| | - Stefano Santabarbara
- Centro
Studi sulla Biologia Cellulare e Molecolare delle Piante, CNR, Via Celoria 26, 20133 Milan, Italy
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Santabarbara S, Bullock B, Rappaport F, Redding KE. Controlling electron transfer between the two cofactor chains of photosystem I by the redox state of one of their components. Biophys J 2016; 108:1537-1547. [PMID: 25809266 DOI: 10.1016/j.bpj.2015.01.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/29/2014] [Accepted: 01/07/2015] [Indexed: 10/23/2022] Open
Abstract
Two functional electron transfer (ET) chains, related by a pseudo-C2 symmetry, are present in the reaction center of photosystem I (PSI). Due to slight differences in the environment around the cofactors of the two branches, there are differences in both the kinetics of ET and the proportion of ET that occurs on the two branches. The strongest evidence that this is indeed the case relied on the observation that the oxidation rates of the reduced phylloquinone (PhQ) cofactor differ by an order of magnitude. Site-directed mutagenesis of residues involved in the respective PhQ-binding sites resulted in a specific alteration of the rates of semiquinone oxidation. Here, we show that the PsaA-F689N mutation results in an ∼100-fold decrease in the observed rate of PhQA(-) oxidation. This is the largest change of PhQA(-) oxidation kinetics observed so far for a single-point mutation, resulting in a lifetime that exceeds that of the terminal electron donor, P700(+). This situation allows a second photochemical charge separation event to be initiated before PhQA(-) has decayed, thereby mimicking in PSI a situation that occurs in type II reaction centers. The results indicate that the presence of PhQA(-) does not impact the overall quantum yield and leads to an almost complete redistribution of the fractional utilization of the two functional ET chains, in favor of the one that does not bear the charged species. The evolutionary implications of these results are also briefly discussed.
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Affiliation(s)
- Stefano Santabarbara
- Department of Chemistry & Biochemistry, Arizona State University, Tempe, Arizona; Institut de Biologie Physico-Chimique, UMR7141 CNRS-UPMC, Paris, France; Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Milano, Italy
| | - Bradford Bullock
- Department of Chemistry, University of Alabama, Tuscaloosa, Alabama
| | - Fabrice Rappaport
- Institut de Biologie Physico-Chimique, UMR7141 CNRS-UPMC, Paris, France.
| | - Kevin E Redding
- Department of Chemistry & Biochemistry, Arizona State University, Tempe, Arizona.
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Santabarbara S, Zucchelli G. Comparative kinetic and energetic modelling of phyllosemiquinone oxidation in Photosystem I. Phys Chem Chem Phys 2016; 18:9687-701. [PMID: 26998536 DOI: 10.1039/c5cp06590a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The oxidation kinetics of phyllo(semi)quinone (PhQ), which acts as an electron transfer (ET) intermediate in the Photosystem I reaction centre, are described by a minimum of two exponential phases, characterised by lifetimes in the 10-30 ns and 150-300 ns ranges. The fastest phase is considered to be dominated by the oxidation of the PhQ molecule coordinated by the PsaB reaction centre subunit (PhQB), and the slowest phase is dominated by the oxidation of the PsaA coordinated PhQ (PhQA). Testing different energetic schemes within a unified theory-based kinetic modelling approach provides reliable limit-values for some of the physical-chemical parameters controlling these ET reactions: (i) the value of ΔG(0) associated with PhQA oxidation is smaller than ∼+30 meV; (ii) the value of the total reorganisation energy (λt) likely exceeds 0.7 eV; (iii) different mean nuclear modes are coupled to PhQB and PhQA oxidation, the former being larger, and both being ≥100 cm(-1).
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Affiliation(s)
- Stefano Santabarbara
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Celoria 26, 20133 Milano, Italy.
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15
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Najdanova M, Janssen GJ, de Groot HJM, Matysik J, Alia A. Analysis of electron donors in photosystems in oxygenic photosynthesis by photo-CIDNP MAS NMR. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2015; 152:261-71. [PMID: 26282679 DOI: 10.1016/j.jphotobiol.2015.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 08/04/2015] [Accepted: 08/05/2015] [Indexed: 10/23/2022]
Abstract
Both photosystem I and photosystem II are considerably similar in molecular architecture but they operate at very different electrochemical potentials. The origin of the different redox properties of these RCs is not yet clear. In recent years, insight was gained into the electronic structure of photosynthetic cofactors through the application of photochemically induced dynamic nuclear polarization (photo-CIDNP) with magic-angle spinning NMR (MAS NMR). Non-Boltzmann populated nuclear spin states of the radical pair lead to strongly enhanced signal intensities that allow one to observe the solid-state photo-CIDNP effect from both photosystem I and II from isolated reaction center of spinach (Spinacia oleracea) and duckweed (Spirodela oligorrhiza) and from the intact cells of the cyanobacterium Synechocystis by (13)C and (15)N MAS NMR. This review provides an overview on the photo-CIDNP MAS NMR studies performed on PSI and PSII that provide important ingredients toward reconstruction of the electronic structures of the donors in PSI and PSII.
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Affiliation(s)
- M Najdanova
- University of Leipzig, Institute of Analytical Chemistry, Johannisallee 29, D-04103 Leipzig, Germany
| | - G J Janssen
- University of Leiden, Leiden Institute of Chemistry, Einsteinweg 55, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - H J M de Groot
- University of Leiden, Leiden Institute of Chemistry, Einsteinweg 55, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - J Matysik
- University of Leipzig, Institute of Analytical Chemistry, Johannisallee 29, D-04103 Leipzig, Germany
| | - A Alia
- University of Leiden, Leiden Institute of Chemistry, Einsteinweg 55, P.O. Box 9502, 2300 RA Leiden, The Netherlands; University of Leipzig, Institute of Medical Physics and Biophysics, Härtelstr. 16-18, D-04107 Leipzig, Germany.
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16
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Caffarri S, Tibiletti T, Jennings RC, Santabarbara S. A comparison between plant photosystem I and photosystem II architecture and functioning. Curr Protein Pept Sci 2015; 15:296-331. [PMID: 24678674 PMCID: PMC4030627 DOI: 10.2174/1389203715666140327102218] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 11/22/2013] [Accepted: 03/16/2014] [Indexed: 01/31/2023]
Abstract
Oxygenic photosynthesis is indispensable both for the development and maintenance of life on earth by converting
light energy into chemical energy and by producing molecular oxygen and consuming carbon dioxide. This latter
process has been responsible for reducing the CO2 from its very high levels in the primitive atmosphere to the present low
levels and thus reducing global temperatures to levels conducive to the development of life. Photosystem I and photosystem
II are the two multi-protein complexes that contain the pigments necessary to harvest photons and use light energy to
catalyse the primary photosynthetic endergonic reactions producing high energy compounds. Both photosystems are
highly organised membrane supercomplexes composed of a core complex, containing the reaction centre where electron
transport is initiated, and of a peripheral antenna system, which is important for light harvesting and photosynthetic activity
regulation. If on the one hand both the chemical reactions catalysed by the two photosystems and their detailed structure
are different, on the other hand they share many similarities. In this review we discuss and compare various aspects of
the organisation, functioning and regulation of plant photosystems by comparing them for similarities and differences as
obtained by structural, biochemical and spectroscopic investigations.
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Affiliation(s)
| | | | | | - Stefano Santabarbara
- Laboratoire de Génétique et de Biophysique des Plantes (LGBP), Aix-Marseille Université, Faculté des Sciences de Luminy, 163 Avenue de Luminy, 13009, Marseille, France.
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McConnell MD, Lowry D, Rowan TN, van Dijk K, Redding KE. Purification and photobiochemical profile of photosystem 1 from a high-salt tolerant, oleaginous Chlorella (Trebouxiophycaea, Chlorophyta). Biochem Cell Biol 2015; 93:199-209. [PMID: 25600216 DOI: 10.1139/bcb-2014-0144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The eukaryotic green alga Chlamydomonas reinhardtii has been studied extensively within the biofuel industry as a model organism, as researchers look towards algae to provide chemical feedstocks (i.e., lipids) for the production of liquid transportation fuels. C. reinhardtii, however, is unsuitable for high-level production of such precursors due to its relatively poor lipid accumulation and fresh-water demand. In this study we offer insight into the primary light harvesting and electron transfer reactions that occur during phototropic growth in a high-salt tolerant strain of Chlorella (a novel strain introduced here as NE1401), a single-celled eukaryotic algae also in the phylum Chlorophyta. Under nutrient starvation many eukaryotic algae increase dramatically the amount of lipids stored in lipid bodies within their cell interiors. Microscopy and lipid analyses indicate that Chlorella sp. NE1401 may become a superior candidate for algal biofuels production. We have purified highly active Photosystem 1 (PS1) complexes to study in vitro, so that we may understand further the photobiochemisty of this promising biofuel producer and how its characteristics compare and contrast with that of the better understood C. reinhardtii. Our findings suggest that the PS1 complex from Chlorella sp. NE1401 demonstrates similar characteristics to that of C. reinhardtii with respect to light-harvesting and electron transfer reactions. We also illustrate that the relative extent of the light state transition performed by Chlorella sp. NE1401 is smaller compared to C. reinhardtii, although they are triggered by the same dynamic light stresses.
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Affiliation(s)
- Michael D McConnell
- Department of Chemistry & Biochemistry and Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, AZ 85287-1604, USA., Department of Biochemistry, University of Nebraska at Lincoln, Lincoln, NE 68588-0664, USA
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Antal TK, Kovalenko IB, Rubin AB, Tyystjärvi E. Photosynthesis-related quantities for education and modeling. PHOTOSYNTHESIS RESEARCH 2013; 117:1-30. [PMID: 24162971 DOI: 10.1007/s11120-013-9945-8] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2013] [Accepted: 10/07/2013] [Indexed: 05/24/2023]
Abstract
A quantitative understanding of the photosynthetic machinery depends largely on quantities, such as concentrations, sizes, absorption wavelengths, redox potentials, and rate constants. The present contribution is a collection of numbers and quantities related mainly to photosynthesis in higher plants. All numbers are taken directly from a literature or database source and the corresponding reference is provided. The numerical values, presented in this paper, provide ranges of values, obtained in specific experiments for specific organisms. However, the presented numbers can be useful for understanding the principles of structure and function of photosynthetic machinery and for guidance of future research.
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Affiliation(s)
- Taras K Antal
- Biological Faculty, Moscow State University, Vorobyevi Gory, 119992, Moscow, Russia
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Santabarbara S, Casazza AP, Ali K, Economou CK, Wannathong T, Zito F, Redding KE, Rappaport F, Purton S. The requirement for carotenoids in the assembly and function of the photosynthetic complexes in Chlamydomonas reinhardtii. PLANT PHYSIOLOGY 2013; 161:535-46. [PMID: 23161889 PMCID: PMC3532283 DOI: 10.1104/pp.112.205260] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
We have investigated the importance of carotenoids on the accumulation and function of the photosynthetic apparatus using a mutant of the green alga Chlamydomonas reinhardtii lacking carotenoids. The FN68 mutant is deficient in phytoene synthase, the first enzyme of the carotenoid biosynthesis pathway, and therefore is unable to synthesize any carotenes and xanthophylls. We find that FN68 is unable to accumulate the light-harvesting complexes associated with both photosystems as well as the RC subunits of photosystem II. The accumulation of the cytochrome b₆f complex is also strongly reduced to a level approximately 10% that of the wild type. However, the residual fraction of assembled cytochrome b₆f complexes exhibits single-turnover electron transfer kinetics comparable to those observed in the wild-type strain. Surprisingly, photosystem I is assembled to significant levels in the absence of carotenoids in FN68 and possesses functional properties that are very similar to those of the wild-type complex.
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Affiliation(s)
- Stefano Santabarbara
- Institute of Structural and Molecular Biology, University College London, London WC1E 6BT, United Kingdom.
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Kargul J, Janna Olmos JD, Krupnik T. Structure and function of photosystem I and its application in biomimetic solar-to-fuel systems. JOURNAL OF PLANT PHYSIOLOGY 2012; 169:1639-1653. [PMID: 22784471 DOI: 10.1016/j.jplph.2012.05.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 05/09/2012] [Accepted: 05/11/2012] [Indexed: 06/01/2023]
Abstract
Photosystem I (PSI) is one of the most efficient biological macromolecular complexes that converts solar energy into condensed energy of chemical bonds. Despite high structural complexity, PSI operates with a quantum yield close to 1.0 and to date, no man-made synthetic system approached this remarkable efficiency. This review highlights recent developments in dissecting molecular structure and function of the prokaryotic and eukaryotic PSI. It also overviews progress in the application of this complex as a natural photocathode for production of hydrogen within the biomimetic solar-to-fuel nanodevices.
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Affiliation(s)
- Joanna Kargul
- Department of Plant Molecular Physiology, University of Warsaw, ul. Miecznikowa 1, 02-096 Warsaw, Poland.
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21
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Santabarbara S, Bailleul B, Redding K, Barber J, Rappaport F, Telfer A. Kinetics of phyllosemiquinone oxidation in the Photosystem I reaction centre of Acaryochloris marina. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1817:328-35. [DOI: 10.1016/j.bbabio.2011.10.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 10/10/2011] [Accepted: 10/11/2011] [Indexed: 11/28/2022]
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Physical Factors of the Environment. Biophysics (Nagoya-shi) 2012. [DOI: 10.1007/978-3-662-45845-7_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Kargul J, Barber J. Structure and Function of Photosynthetic Reaction Centres. MOLECULAR SOLAR FUELS 2011. [DOI: 10.1039/9781849733038-00107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Extensive biochemical, biophysical, molecular biological and structural studies on a wide range of prokaryotic and eukaryotic photosynthetic organisms has revealed common features of their reaction centres where light induced charge separation and stabilization occurs. There is little doubt that all reaction centres have evolved from a common ancestor and have been optimized to maximum efficiency. As such they provide principles that can be used as a blueprint for developing artificial photo-electrochemical catalytic systems to generate solar fuels. This chapter summarises the common features of the organization of cofactors, electron transfer pathways and protein environments of reaction centres of anoxygenic and oxygenic phototrophs. In particular, the latest molecular details derived from X-ray crystallography are discussed in context of the specific catalytic functions of the Type I and Type II reaction centres.
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Affiliation(s)
- Joanna Kargul
- Division of Molecular Biosciences, Faculty of Natural Sciences Imperial College London, London, SW7 2AZ UK
| | - James Barber
- Division of Molecular Biosciences, Faculty of Natural Sciences Imperial College London, London, SW7 2AZ UK
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Yan C, Schofield O, Dubinsky Z, Mauzerall D, Falkowski PG, Gorbunov MY. Photosynthetic energy storage efficiency in Chlamydomonas reinhardtii, based on microsecond photoacoustics. PHOTOSYNTHESIS RESEARCH 2011; 108:215-224. [PMID: 21894460 DOI: 10.1007/s11120-011-9682-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Accepted: 08/15/2011] [Indexed: 05/31/2023]
Abstract
Using a novel, pulsed micro-second time-resolved photoacoustic (PA) instrument, we measured thermal dissipation and energy storage (ES) in the intact cells of wild type (WT) Chlamydomonas reinhardtii, and mutants lacking either PSI or PSII reaction centers (RCs). On this time scale, the kinetic contributions of the thermal expansion component due to heat dissipation of absorbed energy and the negative volume change due to electrostriction induced by charge separation in each of the photosystems could be readily distinguished. Kinetic analysis revealed that PSI and PSII RCs exhibit strikingly different PA signals where PSI is characterized by a strong electrostriction signal and a weak thermal expansion component while PSII has a small electrostriction component and large thermal expansion. The calculated ES efficiencies at ~10 μs were estimated to be 80 ± 5 and 50 ± 13% for PSII-deficient mutants and PSI-deficient mutants, respectively, and 67 ± 2% for WT. The overall ES efficiency was positively correlated with the ratio of PSI to PSI + PSII. Our results suggest that the shallow excitonic trap in PSII limits the efficiency of ES as a result of an evolutionary frozen metabolic framework of two photosystems in all oxygenic photoautotrophs.
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Affiliation(s)
- Chengyi Yan
- Environmental Biophysics and Molecular Ecology Program, Institute of Marine and Coastal Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901, USA
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McCusker CE, McCusker JK. Synthesis and Spectroscopic Characterization of CN-Substituted Bipyridyl Complexes of Ru(II). Inorg Chem 2011; 50:1656-69. [DOI: 10.1021/ic102085b] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Catherine E. McCusker
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - James K. McCusker
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
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Santabarbara S, Kuprov I, Poluektov O, Casal A, Russell CA, Purton S, Evans MCW. Directionality of Electron-Transfer Reactions in Photosystem I of Prokaryotes: Universality of the Bidirectional Electron-Transfer Model. J Phys Chem B 2010; 114:15158-71. [PMID: 20977227 DOI: 10.1021/jp1044018] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stefano Santabarbara
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Ilya Kuprov
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Oleg Poluektov
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Antonio Casal
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Charlotte A. Russell
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Saul Purton
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
| | - Michael C. W. Evans
- Department of Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom; Department of Physics, University of Strathclyde, 107 Rottenrow East, Glasgow G4 0NG, Scotland, United Kingdom; Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom; Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Ave., Argonne, Illinois 60439, United States; and School of Biological
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