1
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Schmitt FJ, Friedrich T. Adaptation processes in Halomicronema hongdechloris, an example of the light-induced optimization of the photosynthetic apparatus on hierarchical time scales. FRONTIERS IN PLANT SCIENCE 2024; 15:1359195. [PMID: 39049856 PMCID: PMC11266139 DOI: 10.3389/fpls.2024.1359195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 06/04/2024] [Indexed: 07/27/2024]
Abstract
Oxygenic photosynthesis in Halomicronema hongdechloris, one of a series of cyanobacteria producing red-shifted Chl f, is adapted to varying light conditions by a range of diverse processes acting over largely different time scales. Acclimation to far-red light (FRL) above 700 nm over several days is mirrored by reversible changes in the Chl f content. In several cyanobacteria that undergo FRL photoacclimation, Chl d and Chl f are directly involved in excitation energy transfer in the antenna system, form the primary donor in photosystem I (PSI), and are also involved in electron transfer within photosystem II (PSII), most probably at the ChlD1 position, with efficient charge transfer happening with comparable kinetics to reaction centers containing Chl a. In H. hongdechloris, the formation of Chl f under FRL comes along with slow adaptive proteomic shifts like the rebuilding of the D1 complex on the time scale of days. On shorter time scales, much faster adaptation mechanisms exist involving the phycobilisomes (PBSs), which mainly contain allophycocyanin upon adaptation to FRL. Short illumination with white, blue, or red light leads to reactive oxygen species-driven mobilization of the PBSs on the time scale of seconds, in effect recoupling the PBSs with Chl f-containing PSII to re-establish efficient excitation energy transfer within minutes. In summary, H. hongdechloris reorganizes PSII to act as a molecular heat pump lifting excited states from Chl f to Chl a on the picosecond time scale in combination with a light-driven PBS reorganization acting on the time scale of seconds to minutes depending on the actual light conditions. Thus, structure-function relationships in photosynthetic energy and electron transport in H. hongdechloris including long-term adaptation processes cover 10-12 to 106 seconds, i.e., 18 orders of magnitude in time.
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Affiliation(s)
- Franz-Josef Schmitt
- Department of Physics, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany
| | - Thomas Friedrich
- Department of Bioenergetics, Technische Universität Berlin, Institute of Chemistry PC 14, Berlin, Germany
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2
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Elias E, Oliver TJ, Croce R. Oxygenic Photosynthesis in Far-Red Light: Strategies and Mechanisms. Annu Rev Phys Chem 2024; 75:231-256. [PMID: 38382567 DOI: 10.1146/annurev-physchem-090722-125847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Oxygenic photosynthesis, the process that converts light energy into chemical energy, is traditionally associated with the absorption of visible light by chlorophyll molecules. However, recent studies have revealed a growing number of organisms capable of using far-red light (700-800 nm) to drive oxygenic photosynthesis. This phenomenon challenges the conventional understanding of the limits of this process. In this review, we briefly introduce the organisms that exhibit far-red photosynthesis and explore the different strategies they employ to harvest far-red light. We discuss the modifications of photosynthetic complexes and their impact on the delivery of excitation energy to photochemical centers and on overall photochemical efficiency. Finally, we examine the solutions employed to drive electron transport and water oxidation using relatively low-energy photons. The findings discussed here not only expand our knowledge of the remarkable adaptation capacities of photosynthetic organisms but also offer insights into the potential for enhancing light capture in crops.
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Affiliation(s)
- Eduard Elias
- Department of Physics and Astronomy, Faculty of Science, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands;
| | - Thomas J Oliver
- Department of Physics and Astronomy, Faculty of Science, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands;
| | - Roberta Croce
- Department of Physics and Astronomy, Faculty of Science, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands;
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3
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Schmitt FJ, Hüls A, Moldenhauer M, Friedrich T. How electron tunneling and uphill excitation energy transfer support photochemistry in Halomicronema hongdechloris. PHOTOSYNTHESIS RESEARCH 2024; 159:273-289. [PMID: 38198121 DOI: 10.1007/s11120-023-01064-4] [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: 05/31/2023] [Accepted: 11/13/2023] [Indexed: 01/11/2024]
Abstract
Halomicronema hongdechloris, the first cyanobacterium reported to produce the red-shifted chlorophyll f (Chl f) upon acclimation to far-red light, demonstrates remarkable adaptability to diverse light conditions. The photosystem II (PS II) of this organism undergoes reversible changes in its Chl f content, ranging from practically zero under white-light culture conditions to a Chl f: Chl a ratio of up to 1:8 when exposed to far-red light (FRL) of 720-730 nm for several days. Our ps time- and wavelength-resolved fluorescence data obtained after excitation of living H. hongdechloris cells indicate that the Soret band of a far-red (FR) chlorophyll involved in charge separation absorbs around 470 nm. At 10 K, the fluorescence decay at 715-720 nm is still fast with a time constant of 165 ps indicating an efficient electron tunneling process. There is efficient excitation energy transfer (EET) from 715-720 nm to 745 nm with the latter resulting from FR Chl f, which mainly functions as light-harvesting pigment upon adaptation to FRL. From there, excitation energy reaches the primary donor in the reaction center of PS II with an energetic uphill EET mechanism inducing charge transfer. The fluorescence data are well explained with a secondary donor PD1 represented by a red-shifted Chl a molecule with characteristic fluorescence around 715 nm and a more red-shifted FR Chl f with fluorescence around 725 nm as primary donor at the ChlD1 or PD2 position.
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Affiliation(s)
- Franz-Josef Schmitt
- Department of Physics, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 3, 06120, Halle (Saale), Germany.
| | - Anne Hüls
- Department of Bioenergetics, Institute of Chemistry PC 14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Marcus Moldenhauer
- Department of Bioenergetics, Institute of Chemistry PC 14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
| | - Thomas Friedrich
- Department of Bioenergetics, Institute of Chemistry PC 14, Technische Universität Berlin, Straße des 17. Juni 135, 10623, Berlin, Germany
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4
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Kosumi D, Bandou-Uotani M, Kato S, Kawakami K, Yonekura K, Kamiya N. Reinvestigation on primary processes of PSII-dimer from Thermosynechococcus vulcanus by femtosecond pump-probe spectroscopy. PHOTOSYNTHESIS RESEARCH 2024; 159:79-91. [PMID: 38363474 DOI: 10.1007/s11120-024-01076-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 01/09/2024] [Indexed: 02/17/2024]
Abstract
Cyanobacterial photosynthetic apparatus efficiently capture sunlight, and the energy is subsequently transferred to photosystem I (PSI) and II (PSII), to produce electrochemical potentials. PSII is a unique membrane protein complex that photo-catalyzes oxidation of water and majorly contains photosynthetic pigments of chlorophyll a and carotenoids. In the present study, the ultrafast energy transfer and charge separation dynamics of PSII from a thermophilic cyanobacterium Thermosynechococcus vulcanus were reinvestigated by femtosecond pump-probe spectroscopic measurements under low temperature and weak intensity excitation condition. The results imply the two possible models of the energy transfers and subsequent charge separation in PSII. One is the previously suggested "transfer-to-trapped limit" model. Another model suggests that the energy transfers from core CP43 and CP47 antennas to the primary electron donor ChlD1 with time-constants of 0.71 ps and 3.28 ps at 140 K (0.17 and 1.33 ps at 296 K), respectively and that the pheophytin anion (PheoD1-) is generated with the time-constant of 43.0 ps at 140 K (14.8 ps at 296 K) upon excitation into the Qy band of chlorophyll a at 670 nm. The secondary electron transfer to quinone QA: PheoD1-QA → PheoD1QA- is observed with the time-constant of 650 ps only at 296 K. On the other hand, an inefficient β-carotene → chlorophyll a energy transfer (33%) occurred after excitation to the S2 state of β-carotene at 500 nm. Instead, the carotenoid triplet state appeared in an ultrafast timescale after excitation at 500 nm.
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Affiliation(s)
- Daisuke Kosumi
- Institute of Industrial Nanomaterials, Kumamoto University, 2-39-1 Kurokami, Chuo-Ku, Kumamoto, 860-8555, Japan.
| | - Miki Bandou-Uotani
- School of Graduate Studies, The Open University of Japan, 2-11 Wakaba, Mihama-Ku, Chiba, 261-8586, Japan
- Division of Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-Ku, Kumamoto, 860-8555, Japan
| | - Shunya Kato
- Department of Physics, Faculty of Science, Kumamoto University, 2-39-1 Kurokami, Chuo-Ku, Kumamoto, 860-8555, Japan
| | - Keisuke Kawakami
- Biostructual Mechanism Laboratory, RIKEN, SPring-8 Center, 1-1-1, Kouto, Sayo, Hyougo, 679-5148, Japan.
| | - Koji Yonekura
- Biostructual Mechanism Laboratory, RIKEN, SPring-8 Center, 1-1-1, Kouto, Sayo, Hyougo, 679-5148, Japan
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-Ku, Sendai, 980-8577, Japan
| | - Nobuo Kamiya
- The OCU Research Center for Artificial Photosynthesis, Osaka Metropolitan University, 3-3-138Sumiyoshi-Ku, SugimotoOsaka City, Osaka, 558-8585, Japan
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5
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Gisriel CJ, Bryant DA, Brudvig GW, Cardona T. Molecular diversity and evolution of far-red light-acclimated photosystem I. FRONTIERS IN PLANT SCIENCE 2023; 14:1289199. [PMID: 38053766 PMCID: PMC10694217 DOI: 10.3389/fpls.2023.1289199] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 10/31/2023] [Indexed: 12/07/2023]
Abstract
The need to acclimate to different environmental conditions is central to the evolution of cyanobacteria. Far-red light (FRL) photoacclimation, or FaRLiP, is an acclimation mechanism that enables certain cyanobacteria to use FRL to drive photosynthesis. During this process, a well-defined gene cluster is upregulated, resulting in changes to the photosystems that allow them to absorb FRL to perform photochemistry. Because FaRLiP is widespread, and because it exemplifies cyanobacterial adaptation mechanisms in nature, it is of interest to understand its molecular evolution. Here, we performed a phylogenetic analysis of the photosystem I subunits encoded in the FaRLiP gene cluster and analyzed the available structural data to predict ancestral characteristics of FRL-absorbing photosystem I. The analysis suggests that FRL-specific photosystem I subunits arose relatively late during the evolution of cyanobacteria when compared with some of the FRL-specific subunits of photosystem II, and that the order Nodosilineales, which include strains like Halomicronema hongdechloris and Synechococcus sp. PCC 7335, could have obtained FaRLiP via horizontal gene transfer. We show that the ancestral form of FRL-absorbing photosystem I contained three chlorophyll f-binding sites in the PsaB2 subunit, and a rotated chlorophyll a molecule in the A0B site of the electron transfer chain. Along with our previous study of photosystem II expressed during FaRLiP, these studies describe the molecular evolution of the photosystem complexes encoded by the FaRLiP gene cluster.
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Affiliation(s)
| | - Donald A. Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, New Haven, CT, United States
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Tanai Cardona
- Department of Life Sciences, Imperial College London, London, United Kingdom
- School of Biological and Behavioural Sciences, Queen Mary University of London, London, United Kingdom
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6
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Silori Y, Willow R, Nguyen HH, Shen G, Song Y, Gisriel CJ, Brudvig GW, Bryant DA, Ogilvie JP. Two-Dimensional Electronic Spectroscopy of the Far-Red-Light Photosystem II Reaction Center. J Phys Chem Lett 2023; 14:10300-10308. [PMID: 37943008 DOI: 10.1021/acs.jpclett.3c02604] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
Understanding the role of specific pigments in primary energy conversion in the photosystem II (PSII) reaction center has been impeded by the spectral overlap of its constituent pigments. When grown in far-red light, some cyanobacteria incorporate chlorophyll-f and chlorophyll-d into PSII, relieving the spectral congestion. We employ two-dimensional electronic spectroscopy to study PSII at 77 K from Synechococcus sp. PCC 7335 cells that were grown in far-red light (FRL-PSII). We observe the formation of a radical pair within ∼3 ps that we assign to ChlD1•-PD1•+. While PheoD1 is thought to act as the primary electron acceptor in PSII from cells grown in visible light, we see no evidence of its involvement, which we attribute to its reduction by dithionite treatment in our samples. Our work demonstrates that primary charge separation occurs between ChlD1 and PD1 in FRL-PSII, suggesting that PD1/PD2 may play an underappreciated role in PSII's charge separation mechanism.
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Affiliation(s)
- Yogita Silori
- Department of Physics and Biophysics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Rhiannon Willow
- Department of Physics and Biophysics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Hoang H Nguyen
- Department of Physics and Biophysics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States
| | - Gaozhong Shen
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Yin Song
- School of Optics and Photonics, Beijing Institute of Technology, 5 Zhongguancun South Street, Haidian District, Beijing, 100081, China
| | - Christopher J Gisriel
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Gary W Brudvig
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Jennifer P Ogilvie
- Department of Physics and Biophysics, University of Michigan, 450 Church Street, Ann Arbor, Michigan 48109, United States
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7
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Boussac A, Sugiura M, Nakamura M, Nagao R, Noguchi T, Viola S, Rutherford AW, Sellés J. Absorption changes in Photosystem II in the Soret band region upon the formation of the chlorophyll cation radical [P D1P D2] . PHOTOSYNTHESIS RESEARCH 2023:10.1007/s11120-023-01049-3. [PMID: 37751034 DOI: 10.1007/s11120-023-01049-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 09/07/2023] [Indexed: 09/27/2023]
Abstract
Flash-induced absorption changes in the Soret region arising from the [PD1PD2]+ state, the chlorophyll cation radical formed upon light excitation of Photosystem II (PSII), were measured in Mn-depleted PSII cores at pH 8.6. Under these conditions, TyrD is i) reduced before the first flash, and ii) oxidized before subsequent flashes. In wild-type PSII, when TyrD● is present, an additional signal in the [PD1PD2]+-minus-[PD1PD2] difference spectrum was observed when compared to the first flash when TyrD is not oxidized. The additional feature was "W-shaped" with troughs at 434 nm and 446 nm. This feature was absent when TyrD was reduced, but was present (i) when TyrD was physically absent (and replaced by phenylalanine) or (ii) when its H-bonding histidine (D2-His189) was physically absent (replaced by a Leucine). Thus, the simple difference spectrum without the double trough feature at 434 nm and 446 nm, seemed to require the native structural environment around the reduced TyrD and its H bonding partners to be present. We found no evidence of involvement of PD1, ChlD1, PheD1, PheD2, TyrZ, and the Cytb559 heme in the W-shaped difference spectrum. However, the use of a mutant of the PD2 axial His ligand, the D2-His197Ala, shows that the PD2 environment seems involved in the formation of "W-shaped" signal.
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Affiliation(s)
- Alain Boussac
- Institut de Biologie Intégrative de la Cellule, UMR9198, CEA Saclay, 91191, Gif-Sur-Yvette, France.
| | - Miwa Sugiura
- Proteo-Science Research Center, and Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-Cho, Matsuyama, Ehime, 790-8577, Japan
| | - Makoto Nakamura
- Proteo-Science Research Center, and Department of Chemistry, Graduate School of Science and Technology, Ehime University, Bunkyo-Cho, Matsuyama, Ehime, 790-8577, Japan
| | - Ryo Nagao
- Faculty of Agriculture, Shizuoka University, Shizuoka, 422-8529, Japan
| | - Takumi Noguchi
- Department of Physics, Graduate School of Science, Nagoya University, Furo-Cho, Chikusa-Ku, Nagoya, 464-8602, Japan
| | - Stefania Viola
- Institut de Biosciences Et Biotechnologies, UMR 7265, Aix-Marseille, CEA Cadarache, Cité des Énergies, 13115, Saint-Paul-Lez-Durance, France
| | | | - Julien Sellés
- Institut de Biologie Physico-Chimique, UMR CNRS 7141 and Sorbonne Université, 13 Rue Pierre Et Marie Curie, 75005, Paris, France
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8
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Pinevich AV, Averina SG. On the Edge of the Rainbow: Red-Shifted Chlorophylls and Far-Red Light Photoadaptation in Cyanobacteria. Microbiology (Reading) 2022. [DOI: 10.1134/s0026261722602019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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9
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From antenna to reaction center: Pathways of ultrafast energy and charge transfer in photosystem II. Proc Natl Acad Sci U S A 2022; 119:e2208033119. [PMID: 36215463 PMCID: PMC9586314 DOI: 10.1073/pnas.2208033119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The photosystem II core complex (PSII-CC) is a photosynthetic complex that contains antenna proteins, which collect energy from sunlight, and a reaction center, which converts the collected energy to redox potential. Understanding the interplay between the antenna proteins and the reaction center will facilitate the development of more efficient solar energy conversion technologies. Here, we study the sub-100-ps dynamics of PSII-CC with two-dimensional electronic-vibrational spectroscopy, which connects energy flows with physical space, allowing a direct mapping of energy transfer pathways. Our results reveal a complex dynamical scheme which includes a specific pathway that connects CP43 to the reaction center. Resolving this pathway experimentally provides insights into the energy conversion processes in natural photosynthesis. The photosystem II core complex (PSII-CC) is the smallest subunit of the oxygenic photosynthetic apparatus that contains core antennas and a reaction center, which together allow for rapid energy transfer and charge separation, ultimately leading to efficient solar energy conversion. However, there is a lack of consensus on the interplay between the energy transfer and charge separation dynamics of the core complex. Here, we report the application of two-dimensional electronic-vibrational (2DEV) spectroscopy to the spinach PSII-CC at 77 K. The simultaneous temporal and spectral resolution afforded by 2DEV spectroscopy facilitates the separation and direct assignment of coexisting dynamical processes. Our results show that the dominant dynamics of the PSII-CC are distinct in different excitation energy regions. By separating the excitation regions, we are able to distinguish the intraprotein dynamics and interprotein energy transfer. Additionally, with the improved resolution, we are able to identify the key pigments involved in the pathways, allowing for a direct connection between dynamical and structural information. Specifically, we show that C505 in CP43 and the peripheral chlorophyll ChlzD1 in the reaction center are most likely responsible for energy transfer from CP43 to the reaction center.
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10
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Langley J, Purchase R, Viola S, Fantuzzi A, Davis GA, Shen JR, Rutherford AW, Krausz E, Cox N. Simulating the low-temperature, metastable electrochromism of Photosystem I: Applications to Thermosynechococcus vulcanus and Chroococcidiopsis thermalis. J Chem Phys 2022; 157:125103. [DOI: 10.1063/5.0100431] [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
Low-temperature, metastable electrochromism has been used as a tool to assign pigments in Photosystem I (PS I) from Thermosynechococcus vulcanus and both the white light (WL) and far-red light (FRL) forms of Chroococcidiopsis thermalis. We find a minimum of seven pigments is required to satisfactorily model the electrochromism of PS I. Using our model, we provide a short list of candidates for the chlorophyll f pigment in FRL C. thermalis that absorbs at 756 nm, whose identity to date has proven to be controversial. Specifically, we propose the linker pigments A40 and B39, and two antenna pigments A26 and B24 as defined by crystal structure 1JB0. The pros and cons of these assignments are discussed, and we propose further experiments to better understand the functioning of FRL C. thermalis.
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Affiliation(s)
- Julien Langley
- Australian National University Research School of Chemistry, Australia
| | - Robin Purchase
- Australian National University Research School of Chemistry, Australia
| | | | | | | | - Jian-Ren Shen
- Research Institute for Interdisciplinary Science, Okayama University, Japan
| | | | - Elmars Krausz
- Australian National University, Australian National University Research School of Chemistry, Australia
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11
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Kimura A, Kitoh-Nishioka H, Aota T, Hamaguchi T, Yonekura K, Kawakami K, Shinzawa-Itoh K, Inoue-Kashino N, Ifuku K, Yamashita E, Kashino Y, Itoh S. Theoretical Model of the Far-Red-Light-Adapted Photosystem I Reaction Center of Cyanobacterium Acaryochloris marina Using Chlorophyll d and the Effect of Chlorophyll Exchange. J Phys Chem B 2022; 126:4009-4021. [PMID: 35617171 DOI: 10.1021/acs.jpcb.2c00869] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A theoretical model of the far-red-light-adapted photosystem I (PSI) reaction center (RC) complex of a cyanobacterium, Acaryochloris marina (AmPSI), was constructed based on the exciton theory and the recently identified molecular structure of AmPSI by Hamaguchi et al. (Nat. Commun., 2021, 12, 2333). A. marina performs photosynthesis under the visible to far-red light (400-750 nm), which is absorbed by chlorophyll d (Chl-d). It is in contrast to the situation of all the other oxygenic photosynthetic processes of cyanobacteria and plants, which contains chlorophyll a (Chl-a) that absorbs only 400-700 nm visible light. AmPSI contains 70 Chl-d, 1 Chl-d', 2 pheophytin a (Pheo-a), and 12 carotenoids in the currently available structure. A special pair of Chl-d/Chl-d' acts as the electron donor (P740) and two Pheo-a act as the primary electron acceptor A0 as the counterparts of P700 and Chl-a, respectively, of Chl-a-type PSIs. The exciton Hamiltonian of AmPSI was constructed considering the excitonic coupling strength and site energy shift of individual pigments using the Poisson-TrESP (P-TrESP) and charge density coupling (CDC) methods. The model was constructed to fit the experimentally measured spectra of absorption and circular dichroism (CD) spectra during downhill/uphill excitation energy transfer processes. The constructed theoretical model of AmPSI was further compared with the Chl-a-type PSI of Thermosynechococcus elongatus (TePSI), which contains only Chl-a and Chl-a'. The functional properties of AmPSI and TePSI were further examined by the in silico exchange of Chl-d by Chl-a in the models.
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Affiliation(s)
- Akihiro Kimura
- Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | | | - Toshimichi Aota
- Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Tasuku Hamaguchi
- Biostructural Mechanism Laboratory, RIKEN SPring-8 Center, 776 Sayo, Hyogo 679-5148, Japan
| | - Koji Yonekura
- Biostructural Mechanism Laboratory, RIKEN SPring-8 Center, 776 Sayo, Hyogo 679-5148, Japan
| | - Keisuke Kawakami
- Biostructural Mechanism Laboratory, RIKEN SPring-8 Center, 776 Sayo, Hyogo 679-5148, Japan
| | - Kyoko Shinzawa-Itoh
- Graduate School of Science, University of Hyogo, Ako-gun, Hyogo 678-1297, Japan
| | | | - Kentaro Ifuku
- Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Eiki Yamashita
- Laboratory of Supramolecular Crystallography, Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan
| | - Yasuhiro Kashino
- Graduate School of Science, University of Hyogo, Ako-gun, Hyogo 678-1297, Japan
| | - Shigeru Itoh
- Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
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12
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Viola S, Roseby W, Santabarbara S, Nürnberg D, Assunção R, Dau H, Sellés J, Boussac A, Fantuzzi A, Rutherford AW. Impact of energy limitations on function and resilience in long-wavelength Photosystem II. eLife 2022; 11:79890. [PMID: 35852834 PMCID: PMC9439682 DOI: 10.7554/elife.79890] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 07/18/2022] [Indexed: 01/06/2023] Open
Abstract
Photosystem II (PSII) uses the energy from red light to split water and reduce quinone, an energy-demanding process based on chlorophyll a (Chl-a) photochemistry. Two types of cyanobacterial PSII can use chlorophyll d (Chl-d) and chlorophyll f (Chl-f) to perform the same reactions using lower energy, far-red light. PSII from Acaryochloris marina has Chl-d replacing all but one of its 35 Chl-a, while PSII from Chroococcidiopsis thermalis, a facultative far-red species, has just 4 Chl-f and 1 Chl-d and 30 Chl-a. From bioenergetic considerations, the far-red PSII were predicted to lose photochemical efficiency and/or resilience to photodamage. Here, we compare enzyme turnover efficiency, forward electron transfer, back-reactions and photodamage in Chl-f-PSII, Chl-d-PSII, and Chl-a-PSII. We show that: (i) all types of PSII have a comparable efficiency in enzyme turnover; (ii) the modified energy gaps on the acceptor side of Chl-d-PSII favour recombination via PD1+Phe- repopulation, leading to increased singlet oxygen production and greater sensitivity to high-light damage compared to Chl-a-PSII and Chl-f-PSII; (iii) the acceptor-side energy gaps in Chl-f-PSII are tuned to avoid harmful back reactions, favouring resilience to photodamage over efficiency of light usage. The results are explained by the differences in the redox tuning of the electron transfer cofactors Phe and QA and in the number and layout of the chlorophylls that share the excitation energy with the primary electron donor. PSII has adapted to lower energy in two distinct ways, each appropriate for its specific environment but with different functional penalties.
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Affiliation(s)
- Stefania Viola
- Department of Life Sciences, Imperial College LondonLondonUnited Kingdom
| | - William Roseby
- Department of Life Sciences, Imperial College LondonLondonUnited Kingdom
| | | | | | | | - Holger Dau
- Physics Department, Freie Universität BerlinBerlinGermany
| | - Julien Sellés
- Institut de Biologie Physico-Chimique, UMR CNRS 7141 and Sorbonne UniversitéParisFrance
| | - Alain Boussac
- Institut de Biologie Intégrative de la Cellule, UMR9198, CEA SaclayGif-Sur-YvetteFrance
| | - Andrea Fantuzzi
- Department of Life Sciences, Imperial College LondonLondonUnited Kingdom
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13
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Gisriel CJ, Shen G, Ho MY, Kurashov V, Flesher DA, Wang J, Armstrong WH, Golbeck JH, Gunner MR, Vinyard DJ, Debus RJ, Brudvig GW, Bryant DA. Structure of a monomeric photosystem II core complex from a cyanobacterium acclimated to far-red light reveals the functions of chlorophylls d and f. J Biol Chem 2022; 298:101424. [PMID: 34801554 PMCID: PMC8689208 DOI: 10.1016/j.jbc.2021.101424] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 11/12/2021] [Accepted: 11/13/2021] [Indexed: 11/26/2022] Open
Abstract
Far-red light (FRL) photoacclimation in cyanobacteria provides a selective growth advantage for some terrestrial cyanobacteria by expanding the range of photosynthetically active radiation to include far-red/near-infrared light (700-800 nm). During this photoacclimation process, photosystem II (PSII), the water:plastoquinone photooxidoreductase involved in oxygenic photosynthesis, is modified. The resulting FRL-PSII is comprised of FRL-specific core subunits and binds chlorophyll (Chl) d and Chl f molecules in place of several of the Chl a molecules found when cells are grown in visible light. These new Chls effectively lower the energy canonically thought to define the "red limit" for light required to drive photochemical catalysis of water oxidation. Changes to the architecture of FRL-PSII were previously unknown, and the positions of Chl d and Chl f molecules had only been proposed from indirect evidence. Here, we describe the 2.25 Å resolution cryo-EM structure of a monomeric FRL-PSII core complex from Synechococcus sp. PCC 7335 cells that were acclimated to FRL. We identify one Chl d molecule in the ChlD1 position of the electron transfer chain and four Chl f molecules in the core antenna. We also make observations that enhance our understanding of PSII biogenesis, especially on the acceptor side of the complex where a bicarbonate molecule is replaced by a glutamate side chain in the absence of the assembly factor Psb28. In conclusion, these results provide a structural basis for the lower energy limit required to drive water oxidation, which is the gateway for most solar energy utilization on earth.
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Affiliation(s)
| | - Gaozhong Shen
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Ming-Yang Ho
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA; Intercollege Graduate Program in Plant Biology, The Pennsylvania State University, University Park, Pennsylvania, USA; Department of Life Science, National Taiwan University, Taipei, Taiwan
| | - Vasily Kurashov
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - David A Flesher
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Jimin Wang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | | | - John H Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA; Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania, USA
| | - Marilyn R Gunner
- Department of Physics, City College of New York, New York, New York, USA
| | - David J Vinyard
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Richard J Debus
- Department of Biochemistry, University of California, Riverside, California, USA
| | - Gary W Brudvig
- Department of Chemistry, Yale University, New Haven, Connecticut, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA.
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, USA; Intercollege Graduate Program in Plant Biology, The Pennsylvania State University, University Park, Pennsylvania, USA.
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14
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Hamaguchi T, Kawakami K, Shinzawa-Itoh K, Inoue-Kashino N, Itoh S, Ifuku K, Yamashita E, Maeda K, Yonekura K, Kashino Y. Structure of the far-red light utilizing photosystem I of Acaryochloris marina. Nat Commun 2021; 12:2333. [PMID: 33879791 PMCID: PMC8058080 DOI: 10.1038/s41467-021-22502-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 03/18/2021] [Indexed: 01/09/2023] Open
Abstract
Acaryochloris marina is one of the cyanobacterial species that can use far-red light to drive photochemical reactions for oxygenic photosynthesis. Here, we report the structure of A. marina photosystem I (PSI) reaction center, determined by cryo-electron microscopy at 2.58 Å resolution. The structure reveals an arrangement of electron carriers and light-harvesting pigments distinct from other type I reaction centers. The paired chlorophyll, or special pair (also referred to as P740 in this case), is a dimer of chlorophyll d and its epimer chlorophyll d'. The primary electron acceptor is pheophytin a, a metal-less chlorin. We show the architecture of this PSI reaction center is composed of 11 subunits and we identify key components that help explain how the low energy yield from far-red light is efficiently utilized for driving oxygenic photosynthesis.
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Affiliation(s)
- Tasuku Hamaguchi
- Biostructural Mechanism Laboratory, RIKEN SPring-8 Center, Sayo, Hyogo, Japan
| | - Keisuke Kawakami
- Research Center for Artificial Photosynthesis (ReCAP), Osaka City University, Sumiyoshi-ku, Osaka, Japan.
- Biostructural Mechanism Laboratory, RIKEN SPring-8 Center, Sayo, Hyogo, Japan.
| | | | | | - Shigeru Itoh
- Department of Physics, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Kentaro Ifuku
- Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Eiki Yamashita
- Laboratory of Supramolecular Crystallography, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Kou Maeda
- Graduate School of Life Science, University of Hyogo, Ako-gun, Hyogo, Japan
| | - Koji Yonekura
- Biostructural Mechanism Laboratory, RIKEN SPring-8 Center, Sayo, Hyogo, Japan.
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Aoba-ku, Sendai, Japan.
| | - Yasuhiro Kashino
- Graduate School of Life Science, University of Hyogo, Ako-gun, Hyogo, Japan.
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15
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Gisriel CJ, Huang HL, Reiss KM, Flesher DA, Batista VS, Bryant DA, Brudvig GW, Wang J. Quantitative assessment of chlorophyll types in cryo-EM maps of photosystem I acclimated to far-red light. BBA ADVANCES 2021; 1:100019. [PMID: 37082022 PMCID: PMC10074859 DOI: 10.1016/j.bbadva.2021.100019] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Chlorophyll cofactors are vital for the metabolism of photosynthetic organisms. Cryo-electron microscopy (cryo-EM) has been used to elucidate molecular structures of pigment-protein complexes, but the minor structural differences between multiple types of chlorophylls make them difficult to distinguish in cryo-EM maps. This is exemplified by inconsistencies in the assignments of chlorophyll f molecules in structures of photosystem I acclimated to far-red light (FRL-PSI). A quantitative assessment of chlorophyll substituents in cryo-EM maps was used to identify chlorophyll f-binding sites in structures of FRL-PSI from two cyanobacteria. The two cryo-EM maps provide direct evidence for chlorophyll f-binding at two and three binding sites, respectively, and three more sites in each structure exhibit strong indirect evidence for chlorophyll f-binding. Common themes in chlorophyll f-binding are described that clarify the current understanding of the molecular basis for FRL photoacclimation in photosystems.
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16
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Sirohiwal A, Neese F, Pantazis DA. Protein Matrix Control of Reaction Center Excitation in Photosystem II. J Am Chem Soc 2020; 142:18174-18190. [PMID: 33034453 PMCID: PMC7582616 DOI: 10.1021/jacs.0c08526] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Indexed: 02/06/2023]
Abstract
Photosystem II (PSII) is a multisubunit pigment-protein complex that uses light-induced charge separation to power oxygenic photosynthesis. Its reaction center chromophores, where the charge transfer cascade is initiated, are arranged symmetrically along the D1 and D2 core polypeptides and comprise four chlorophyll (PD1, PD2, ChlD1, ChlD2) and two pheophytin molecules (PheoD1 and PheoD2). Evolution favored productive electron transfer only via the D1 branch, with the precise nature of primary excitation and the factors that control asymmetric charge transfer remaining under investigation. Here we present a detailed atomistic description for both. We combine large-scale simulations of membrane-embedded PSII with high-level quantum-mechanics/molecular-mechanics (QM/MM) calculations of individual and coupled reaction center chromophores to describe reaction center excited states. We employ both range-separated time-dependent density functional theory and the recently developed domain based local pair natural orbital (DLPNO) implementation of the similarity transformed equation of motion coupled cluster theory with single and double excitations (STEOM-CCSD), the first coupled cluster QM/MM calculations of the reaction center. We find that the protein matrix is exclusively responsible for both transverse (chlorophylls versus pheophytins) and lateral (D1 versus D2 branch) excitation asymmetry, making ChlD1 the chromophore with the lowest site energy. Multipigment calculations show that the protein matrix renders the ChlD1 → PheoD1 charge-transfer the lowest energy excitation globally within the reaction center, lower than any pigment-centered local excitation. Remarkably, no low-energy charge transfer states are located within the "special pair" PD1-PD2, which is therefore excluded as the site of initial charge separation in PSII. Finally, molecular dynamics simulations suggest that modulation of the electrostatic environment due to protein conformational flexibility enables direct excitation of low-lying charge transfer states by far-red light.
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Affiliation(s)
- Abhishek Sirohiwal
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
- Fakultät
für Chemie und Biochemie, Ruhr-Universität
Bochum, 44780 Bochum, Germany
| | - Frank Neese
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Dimitrios A. Pantazis
- Max-Planck-Institut
für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany
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