1
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Caro L, Wei AD, Thomas CA, Posch G, Uremis A, Franzi MC, Abell SJ, Laszlo AH, Gundlach JH, Ramirez JM, Ailion M. An animal toxin-antidote system kills cells by creating a novel cation channel. PLoS Biol 2025; 23:e3003182. [PMID: 40424258 DOI: 10.1371/journal.pbio.3003182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2024] [Accepted: 04/28/2025] [Indexed: 05/29/2025] Open
Abstract
Toxin-antidote systems are selfish genetic elements composed of a linked toxin and antidote. The peel-1 zeel-1 toxin-antidote system in C. elegans consists of a transmembrane toxin protein PEEL-1 which acts cell autonomously to kill cells. Here we investigate the molecular mechanism of PEEL-1 toxicity. We find that PEEL-1 requires a small membrane protein, PMPL-1, for toxicity. Together, PEEL-1 and PMPL-1 are sufficient for toxicity in a heterologous system, HEK293T cells, and cause cell swelling and increased cell permeability to monovalent cations. Using purified proteins, we show that PEEL-1 and PMPL-1 allow ion flux through lipid bilayers and generate currents which resemble ion channel gating. Our work suggests that PEEL-1 kills cells by co-opting PMPL-1 and creating a cation channel.
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Affiliation(s)
- Lews Caro
- Molecular and Cellular Biology Ph.D. Program, University of Washington, Seattle, Washington, United States of America
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - Aguan D Wei
- Norcliffe Foundation Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington, United States of America
| | - Christopher A Thomas
- Department of Physics, University of Washington, Seattle, Washington, United States of America
| | - Galen Posch
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - Ahmet Uremis
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
| | - Michaela C Franzi
- Department of Physics, University of Washington, Seattle, Washington, United States of America
| | - Sarah J Abell
- Department of Physics, University of Washington, Seattle, Washington, United States of America
| | - Andrew H Laszlo
- Department of Physics, University of Washington, Seattle, Washington, United States of America
| | - Jens H Gundlach
- Department of Physics, University of Washington, Seattle, Washington, United States of America
| | - Jan-Marino Ramirez
- Norcliffe Foundation Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington, United States of America
- Department of Neurological Surgery, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Michael Ailion
- Molecular and Cellular Biology Ph.D. Program, University of Washington, Seattle, Washington, United States of America
- Department of Biochemistry, University of Washington, Seattle, Washington, United States of America
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2
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Niedzwiedzki DM, Dadwal A, Chiu PL, Liu H. Triplet-State Dynamics of Bacteriochlorophyll a in the Fenna-Matthews-Olson (FMO) Complex and Its Modulation by PscB, a Subunit in the Reaction Center of Chlorobaculum tepidum. J Phys Chem B 2025; 129:4309-4319. [PMID: 40304054 DOI: 10.1021/acs.jpcb.5c00394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2025]
Abstract
In this study, the triplet-state properties of BChl a in the Fenna-Matthews-Olson (FMO) light-harvesting complex were interrogated in the absence and presence of PscB, a subunit of the Cba. tepidum reaction center (RC), at room temperature and at 77 K. Application of nanosecond time-resolved transient absorption spectroscopy supports a model in which the pathway of the triplet excitation decay within FMO has two phases, with a fast lifetime of 2.58 μs (0.57 μs at 77 K) and a slow lifetime of 44.8 μs (44.1 μs at 77 K) in the FMO-only sample. Reconstitution of PscB and FMO, however, alters the spectral signatures of BChl a excitons uniquely at 815 nm in the steady-state spectrum at 77 K. Additionally, the triplet-state lifetime of BChl a in the FMO-PscB complex shortens by almost 40% to 28.1 μs at 77 K. The two FMO trimers asymmetrically interfacing with the homodimeric RC wire excitation energy from the chlorosome to the latter. Our data supports that the single central PscB, besides its redox active roles as the electron mediators to ferredoxin, is highly plausibly involved in fine-tuning the asymmetric excitation energy transfer from two branches of FMO to the RC in green sulfur bacteria.
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Affiliation(s)
- Dariusz M Niedzwiedzki
- Center for Solar Energy and Energy Storage, Washington University in St. Louis, St. Louis, Missouri 63130, United States
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Anica Dadwal
- Department of Biology, Saint Louis University, St. Louis, Missouri 63103, United States
| | - Po-Lin Chiu
- School of Molecular Sciences & Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, Arizona 85287, United States
| | - Haijun Liu
- Department of Biology, Saint Louis University, St. Louis, Missouri 63103, United States
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3
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Li R, Liu X, Wu G, Li G, Chen JH, Jiang H, Dong H. Pyrite stimulates the growth and sulfur oxidation capacity of anoxygenic phototrophic sulfur bacteria in euxinic environments. SCIENCE ADVANCES 2025; 11:eadu7080. [PMID: 40249799 PMCID: PMC12007567 DOI: 10.1126/sciadv.adu7080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2024] [Accepted: 03/14/2025] [Indexed: 04/20/2025]
Abstract
Anoxygenic phototrophic sulfur bacteria flourish in contemporary and ancient euxinic environments, driving the biogeochemical cycles of carbon and sulfur. However, it is unclear how these strict anaerobes meet their high demand for iron in iron-depleted environments. Here, we report that pyrite, a widespread and highly stable iron sulfide mineral in anoxic, low-temperature environments, can support the growth and metabolic activity of anoxygenic phototrophic sulfur bacteria by serving as the sole iron source under iron-depleted conditions. Transcriptomic and proteomic analyses revealed that pyrite addition substantially up-regulated genes and protein expression involved in photosynthesis, sulfur metabolism, and biosynthesis of organics. Anoxic microbial oxidation of pyritic sulfur and consequent destabilization of the pyrite structure were postulated to facilitate microbial iron acquisition. These findings advance our understanding of the survival strategies of anaerobes in iron-depleted environments and are important for revealing the previously underappreciated bioavailability of pyritic iron in anoxic environments and anoxic weathering of pyrite.
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Affiliation(s)
- Runjie Li
- Center for Geomicrobiology and Biogeochemistry Research, State Key Laboratory of Geomicrobiology and Environmental Changes, China University of Geosciences (Beijing), Beijing 100083, China
- School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China
| | - Xiaolei Liu
- School of Ocean Sciences, China University of Geosciences (Beijing), Beijing 100083, China
- Key Laboratory of Polar Geology and Marine Mineral Resources, China University of Geosciences (Beijing), Beijing 100083, China
| | - Geng Wu
- State Key Laboratory of Geomicrobiology and Environmental Changes, China University of Geosciences, Wuhan 430074, China
| | - Gaoyuan Li
- Center for Geomicrobiology and Biogeochemistry Research, State Key Laboratory of Geomicrobiology and Environmental Changes, China University of Geosciences (Beijing), Beijing 100083, China
| | - Jing-Hua Chen
- College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hongchen Jiang
- School of Ocean Sciences, China University of Geosciences (Beijing), Beijing 100083, China
- Key Laboratory of Polar Geology and Marine Mineral Resources, China University of Geosciences (Beijing), Beijing 100083, China
| | - Hailiang Dong
- Center for Geomicrobiology and Biogeochemistry Research, State Key Laboratory of Geomicrobiology and Environmental Changes, China University of Geosciences (Beijing), Beijing 100083, China
- Frontiers Science Center for Deep-time Digital Earth, China University of Geosciences (Beijing), Beijing 100083, China
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4
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Tsukatani Y, Azai C, Noji T, Kawai S, Sugimoto S, Shimamura S, Shimane Y, Harada J, Mizoguchi T, Tamiaki H, Masuda S. Genes for the Type-I Reaction Center and Galactolipid Synthesis are Required for Chlorophyll a Accumulation in a Purple Photosynthetic Bacterium. PLANT & CELL PHYSIOLOGY 2025; 66:204-213. [PMID: 39030709 DOI: 10.1093/pcp/pcae076] [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: 03/28/2024] [Revised: 06/18/2024] [Accepted: 07/19/2024] [Indexed: 07/21/2024]
Abstract
Anoxygenic photosynthesis is diversified into two classes: chlorophototrophy based on a bacterial type-I or type-II reaction center (RC). Whereas the type-I RC contains both bacteriochlorophyll and chlorophyll, type-II RC-based phototrophy relies only on bacteriochlorophyll. However, type-II phototrophic bacteria theoretically have the potential to produce chlorophyll a by the addition of an enzyme, chlorophyll synthase, because the direct precursor for the enzyme, chlorophyllide a, is produced as an intermediate of BChl a biosynthesis. In this study, we attempted to modify the type-II proteobacterial phototroph Rhodovulum sulfidophilum to produce chlorophyll a by introducing chlorophyll synthase, which catalyzes the esterification of a diterpenoid group to chlorophyllide a thereby producing chlorophyll a. However, the resulting strain did not accumulate chlorophyll a, perhaps due to the absence of endogenous chlorophyll a-binding proteins. We further heterologously incorporated genes encoding the type-I RC complex to provide a target for chlorophyll a. Heterologous expression of type-I RC subunits, chlorophyll synthase and galactolipid synthase successfully afforded detectable accumulation of chlorophyll a in Rdv. sulfidophilum. This suggests that the type-I RC can work to accumulate chlorophyll a and that galactolipids are likely necessary for the type-I RC assembly. The evolutionary acquisition of type-I RCs could be related to prior or concomitant acquisition of galactolipids and chlorophylls.
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Affiliation(s)
- Yusuke Tsukatani
- Biogeochemistry Research Center, Research Institute for Marine Resources Utilization, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima-cho, Yokosuka, Kanagawa, 237-0061 Japan
- Institute for Extra-cutting-edge Science and Technology Avant-garde Research (X-star), JAMSTEC, Yokosuka, Kanagawa, 237-0061 Japan
| | - Chihiro Azai
- Faculty of Science and Engineering, Chuo University, Tokyo, 112-8551 Japan
- Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, 525-8577 Japan
| | - Tomoyasu Noji
- The OCU Advanced Research Institute for Natural Science and Technology (OCARINA), Osaka City University, Osaka, 558-8585 Japan
| | - Shigeru Kawai
- Biogeochemistry Research Center, Research Institute for Marine Resources Utilization, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima-cho, Yokosuka, Kanagawa, 237-0061 Japan
- Institute for Extra-cutting-edge Science and Technology Avant-garde Research (X-star), JAMSTEC, Yokosuka, Kanagawa, 237-0061 Japan
| | - Saori Sugimoto
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Kanagawa, 226-8501 Japan
| | - Shigeru Shimamura
- Institute for Extra-cutting-edge Science and Technology Avant-garde Research (X-star), JAMSTEC, Yokosuka, Kanagawa, 237-0061 Japan
| | - Yasuhiro Shimane
- Institute for Extra-cutting-edge Science and Technology Avant-garde Research (X-star), JAMSTEC, Yokosuka, Kanagawa, 237-0061 Japan
| | - Jiro Harada
- Department of Medical Biochemistry, Kurume University School of Medicine, Kurume, Fukuoka, 830-0011 Japan
| | - Tadashi Mizoguchi
- Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, 525-8577 Japan
| | - Hitoshi Tamiaki
- Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, 525-8577 Japan
| | - Shinji Masuda
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Kanagawa, 226-8501 Japan
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5
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Kushkevych I, Procházka V, Vítězová M, Dordević D, Abd El-Salam M, Rittmann SKMR. Anoxygenic photosynthesis with emphasis on green sulfur bacteria and a perspective for hydrogen sulfide detoxification of anoxic environments. Front Microbiol 2024; 15:1417714. [PMID: 39056005 PMCID: PMC11269200 DOI: 10.3389/fmicb.2024.1417714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 06/12/2024] [Indexed: 07/28/2024] Open
Abstract
The bacterial light-dependent energy metabolism can be divided into two types: oxygenic and anoxygenic photosynthesis. Bacterial oxygenic photosynthesis is similar to plants and is characteristic for cyanobacteria. Bacterial anoxygenic photosynthesis is performed by anoxygenic phototrophs, especially green sulfur bacteria (GSB; family Chlorobiaceae) and purple sulfur bacteria (PSB; family Chromatiaceae). In anoxygenic photosynthesis, hydrogen sulfide (H2S) is used as the main electron donor, which differs from plants or cyanobacteria where water is the main source of electrons. This review mainly focuses on the microbiology of GSB, which may be found in water or soil ecosystems where H2S is abundant. GSB oxidize H2S to elemental sulfur. GSB possess special structures-chlorosomes-wherein photosynthetic pigments are located. Chlorosomes are vesicles that are surrounded by a lipid monolayer that serve as light-collecting antennas. The carbon source of GSB is carbon dioxide, which is assimilated through the reverse tricarboxylic acid cycle. Our review provides a thorough introduction to the comparative eco-physiology of GSB and discusses selected application possibilities of anoxygenic phototrophs in the fields of environmental management, bioremediation, and biotechnology.
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Affiliation(s)
- Ivan Kushkevych
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
| | - Vít Procházka
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
| | - Monika Vítězová
- Department of Experimental Biology, Faculty of Science, Masaryk University, Brno, Czechia
| | - Dani Dordević
- Department of Plant Origin Foodstuffs Hygiene and Technology, Faculty of Veterinary Hygiene and Ecology, University of Veterinary Sciences, Brno, Czechia
| | - Mohamed Abd El-Salam
- Department of Pharmacognosy, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa, Egypt
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Simon K.-M. R. Rittmann
- Archaea Physiology & Biotechnology Group, Department of Functional and Evolutionary Ecology, Universität Wien, Wien, Austria
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6
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Caro L, Wei AD, Thomas CA, Posch G, Uremis A, Franzi MC, Abell SJ, Laszlo AH, Gundlach JH, Ramirez JM, Ailion M. Mechanism of an animal toxin-antidote system. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.11.598564. [PMID: 38915716 PMCID: PMC11195288 DOI: 10.1101/2024.06.11.598564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Toxin-antidote systems are selfish genetic elements composed of a linked toxin and antidote. The peel-1 zeel-1 toxin-antidote system in C. elegans consists of a transmembrane toxin protein PEEL-1 which acts cell autonomously to kill cells. Here we investigate the molecular mechanism of PEEL-1 toxicity. We find that PEEL-1 requires a small membrane protein, PMPL-1, for toxicity. Together, PEEL-1 and PMPL-1 are sufficient for toxicity in a heterologous system, HEK293T cells, and cause cell swelling and increased cell permeability to monovalent cations. Using purified proteins, we show that PEEL-1 and PMPL-1 allow ion flux through lipid bilayers and generate currents which resemble ion channel gating. Our work suggests that PEEL-1 kills cells by co-opting PMPL-1 and creating a cation channel.
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Affiliation(s)
- Lews Caro
- Molecular and Cellular Biology Ph.D. Program, University of Washington; Seattle, WA 98195, USA
- Department of Biochemistry, University of Washington; Seattle, WA 91895, USA
| | - Aguan D. Wei
- Norcliffe Foundation Center for Integrative Brain Research, Seattle Children’s Research Institute; Seattle, WA 98101, USA
| | | | - Galen Posch
- Department of Biochemistry, University of Washington; Seattle, WA 91895, USA
| | - Ahmet Uremis
- Department of Biochemistry, University of Washington; Seattle, WA 91895, USA
| | | | - Sarah J. Abell
- Department of Physics, University of Washington; Seattle, WA 91895, USA
| | - Andrew H. Laszlo
- Department of Physics, University of Washington; Seattle, WA 91895, USA
| | - Jens H. Gundlach
- Department of Physics, University of Washington; Seattle, WA 91895, USA
| | - Jan-Marino Ramirez
- Norcliffe Foundation Center for Integrative Brain Research, Seattle Children’s Research Institute; Seattle, WA 98101, USA
- Department of Neurological Surgery, University of Washington School of Medicine; Seattle, WA 98104, USA
| | - Michael Ailion
- Molecular and Cellular Biology Ph.D. Program, University of Washington; Seattle, WA 98195, USA
- Department of Biochemistry, University of Washington; Seattle, WA 91895, USA
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7
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Lyratzakis A, Daskalakis V, Xie H, Tsiotis G. The synergy between the PscC subunits for electron transfer to the P 840 special pair in Chlorobaculum tepidum. PHOTOSYNTHESIS RESEARCH 2024; 160:87-96. [PMID: 38625595 PMCID: PMC11108878 DOI: 10.1007/s11120-024-01093-7] [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: 12/13/2023] [Accepted: 03/08/2024] [Indexed: 04/17/2024]
Abstract
The primary photochemical reaction of photosynthesis in green sulfur bacteria occurs in the homodimer PscA core proteins by a special chlorophyll pair. The light induced excited state of the special pair producing P840+ is rapidly reduced by electron transfer from one of the two PscC subunits. Molecular dynamics (MD) simulations are combined with bioinformatic tools herein to provide structural and dynamic insight into the complex between the two PscA core proteins and the two PscC subunits. The microscopic dynamic model involves extensive sampling at atomic resolution and at a cumulative time-scale of 22µs and reveals well defined protein-protein interactions. The membrane complex is composed of the two PscA and the two PscC subunits and macroscopic connections are revealed within a putative electron transfer pathway from the PscC subunit to the special pair P840 located within the PscA subunits. Our results provide a structural basis for understanding the electron transport to the homodimer RC of the green sulfur bacteria. The MD based approach can provide the basis to further probe the PscA-PscC complex dynamics and observe electron transfer therein at the quantum level. Furthermore, the transmembrane helices of the different PscC subunits exert distinct dynamics in the complex.
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Affiliation(s)
- Alexandros Lyratzakis
- Department of Chemistry, School of Science and Engineering, University of Crete, Heraklion, 70013, Greece
| | - Vangelis Daskalakis
- Department of Chemical Engineering, School of Engineering, University of Patras, Rion, Patras, 26504, Greece
| | - Hao Xie
- Max Planck Institute of Biophysics, 60438, Frankfurt am Main, Germany
| | - Georgios Tsiotis
- Department of Chemistry, School of Science and Engineering, University of Crete, Heraklion, 70013, Greece.
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8
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Nelson N. Investigating the Balance between Structural Conservation and Functional Flexibility in Photosystem I. Int J Mol Sci 2024; 25:5073. [PMID: 38791114 PMCID: PMC11121529 DOI: 10.3390/ijms25105073] [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: 02/27/2024] [Revised: 04/16/2024] [Accepted: 04/30/2024] [Indexed: 05/26/2024] Open
Abstract
Photosynthesis, as the primary source of energy for all life forms, plays a crucial role in maintaining the global balance of energy, entropy, and enthalpy in living organisms. Among its various building blocks, photosystem I (PSI) is responsible for light-driven electron transfer, crucial for generating cellular reducing power. PSI acts as a light-driven plastocyanin-ferredoxin oxidoreductase and is situated in the thylakoid membranes of cyanobacteria and the chloroplasts of eukaryotic photosynthetic organisms. Comprehending the structure and function of the photosynthetic machinery is essential for understanding its mode of action. New insights are offered into the structure and function of PSI and its associated light-harvesting proteins, with a specific focus on the remarkable structural conservation of the core complex and high plasticity of the peripheral light-harvesting complexes.
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Affiliation(s)
- Nathan Nelson
- Department of Biochemistry and Molecular Biology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
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9
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Kimura A, Kitoh-Nishioka H, Kondo T, Oh-Oka H, Itoh S, Azai C. Experimental and Theoretical Mutation of Exciton States on the Smallest Type-I Photosynthetic Reaction Center Complex of a Green Sulfur Bacterium Chlorobaclum tepidum. J Phys Chem B 2024; 128:731-743. [PMID: 38198639 DOI: 10.1021/acs.jpcb.3c07424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
The exciton states on the smallest type-I photosynthetic reaction center complex of a green sulfur bacterium Chlorobaculum tepidum (GsbRC) consisting of 26 bacteriochlorophylls a (BChl a) and four chlorophylls a (Chl a) located on the homodimer of two PscA reaction center polypeptides were investigated. This analysis involved the study of exciton states through a combination of theoretical modeling and the genetic removal of BChl a pigments at eight sites. (1) A theoretical model of the pigment assembly exciton state on GsbRC was constructed using Poisson TrESP (P-TrESP) and charge density coupling (CDC) methods based on structural information. The model reproduced the experimentally obtained absorption spectrum, circular dichroism spectrum, and excitation transfer dynamics, as well as explained the effects of mutation. (2) Eight BChl a molecules at different locations on the GsbRC were selectively removed by genetic exchange of the His residue, which ligates the central Mg atom of BChl a, with the Leu residue on either one or two PscAs in the RC. His locations are conserved among all type-I RC plant polypeptide, cyanobacteria, and bacteria amino acid sequences. (3) Purified mutant-GsbRCs demonstrated distinct absorption and fluorescence spectra at 77 K, which were different from each other, suggesting successful pigment removal. (4) The same mutations were applied to the constructed theoretical model to analyze the outcomes of these mutations. (5) The combination of theoretical predictions and experimental mutations based on structural information is a new tool for studying the function and evolution of photosynthetic reaction centers.
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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
| | - Hirotaka Kitoh-Nishioka
- Department of Energy and Materials, Faculty of Science and Engineering, Kindai University, Osaka 577-8502, Japan
| | - Toru Kondo
- School of Life Science and Technology, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8550, Japan
| | - Hirozo Oh-Oka
- Department of Biological Sciences, Graduate School of Science, Osaka University, Osaka 560-0043, Japan
| | - Shigeru Itoh
- Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Chihiro Azai
- Department of Biological Sciences, Faculty of Science and Engineering, Chuo University, Tokyo 112-8551, Japan
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10
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Oyagi K, Ogasawara S, Tamiaki H. Linker-length dependent intra/intermolecular coordination of synthetic zinc chlorophyll-a derivatives bearing a pyridine terminal in the C132-substituent. Tetrahedron 2023. [DOI: 10.1016/j.tet.2023.133334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
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11
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Structure of the Acidobacteria homodimeric reaction center bound with cytochrome c. Nat Commun 2022; 13:7745. [PMID: 36517472 PMCID: PMC9751088 DOI: 10.1038/s41467-022-35460-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 12/02/2022] [Indexed: 12/23/2022] Open
Abstract
Photosynthesis converts light energy to chemical energy to fuel life on earth. Light energy is harvested by antenna pigments and transferred to reaction centers (RCs) to drive the electron transfer (ET) reactions. Here, we present cryo-electron microscopy (cryo-EM) structures of two forms of the RC from the microaerophilic Chloracidobacterium thermophilum (CabRC): one containing 10 subunits, including two different cytochromes; and the other possessing two additional subunits, PscB and PscZ. The larger form contained 2 Zn-bacteriochlorophylls, 16 bacteriochlorophylls, 10 chlorophylls, 2 lycopenes, 2 hemes, 3 Fe4S4 clusters, 12 lipids, 2 Ca2+ ions and 6 water molecules, revealing a type I RC with an ET chain involving two hemes and a hybrid antenna containing bacteriochlorophylls and chlorophylls. Our results provide a structural basis for understanding the excitation energy and ET within the CabRC and offer evolutionary insights into the origin and adaptation of photosynthetic RCs.
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