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Rankelytė G, Gelzinis A, Robert B, Valkunas L, Chmeliov J. Environment-dependent chlorophyll-chlorophyll charge transfer states in Lhca4 pigment-protein complex. FRONTIERS IN PLANT SCIENCE 2024; 15:1412750. [PMID: 39170787 PMCID: PMC11335733 DOI: 10.3389/fpls.2024.1412750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 07/02/2024] [Indexed: 08/23/2024]
Abstract
Photosystem I (PSI) light-harvesting antenna complexes LHCI contain spectral forms that absorb and emit photons of lower energy than that of its primary electron donor, P700. The most red-shifted fluorescence is associated with the Lhca4 complex. It has been suggested that this red emission is related to the inter-chlorophyll charge transfer (CT) states. In this work we present a systematic quantum-chemical study of the CT states in Lhca4, accounting for the influence of the protein environment by estimating the electrostatic interactions. We show that significant energy shifts result from these interactions and propose that the emission of the Lhca4 complex is related not only to the previously proposed a603+-a608- state, but also to the a602+-a603- state. We also investigate how different protonation patterns of protein amino acids affect the energetics of the CT states.
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Affiliation(s)
- Gabrielė Rankelytė
- Institute of Chemical Physics, Faculty of Physics, Vilnius University, Vilnius, Lithuania
- Department of Molecular Compound Physics, Center for Physical Sciences and Technology, Vilnius, Lithuania
| | - Andrius Gelzinis
- Institute of Chemical Physics, Faculty of Physics, Vilnius University, Vilnius, Lithuania
- Department of Molecular Compound Physics, Center for Physical Sciences and Technology, Vilnius, Lithuania
| | - Bruno Robert
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell, Gif-sur-Yvette, France
| | - Leonas Valkunas
- Department of Molecular Compound Physics, Center for Physical Sciences and Technology, Vilnius, Lithuania
| | - Jevgenij Chmeliov
- Institute of Chemical Physics, Faculty of Physics, Vilnius University, Vilnius, Lithuania
- Department of Molecular Compound Physics, Center for Physical Sciences and Technology, Vilnius, Lithuania
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2
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Li X, Yang G, Yuan X, Wu F, Wang W, Shen JR, Kuang T, Qin X. Structural elucidation of vascular plant photosystem I and its functional implications. FUNCTIONAL PLANT BIOLOGY : FPB 2022; 49:432-443. [PMID: 34637699 DOI: 10.1071/fp21077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 09/13/2021] [Indexed: 06/13/2023]
Abstract
In vascular plants, bryophytes and algae, the photosynthetic light reaction takes place in the thylakoid membrane where two transmembrane supercomplexes PSII and PSI work together with cytochrome b 6 f and ATP synthase to harvest the light energy and produce ATP and NADPH. Vascular plant PSI is a 600-kDa protein-pigment supercomplex, the core complex of which is partly surrounded by peripheral light-harvesting complex I (LHCI) that captures sunlight and transfers the excitation energy to the core to be used for charge separation. PSI is unique mainly in absorption of longer-wavelengths than PSII, fast excitation energy transfer including uphill energy transfer, and an extremely high quantum efficiency. From the early 1980s, a lot of effort has been dedicated to structural and functional studies of PSI-LHCI, leading to the current understanding of how more than 200 cofactors are kept at the correct distance and geometry to facilitate fast energy transfer in this supercomplex at an atomic level. In this review, we review the history of studies on vascular plant PSI-LHCI, summarise the present research progress on its structure, and present some new and further questions to be answered in future studies.
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Affiliation(s)
- Xiuxiu Li
- School of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China; and School of Biological Science and Technology, University of Jinan, Jinan 250022, China
| | - Gongxian Yang
- School of Biological Science and Technology, University of Jinan, Jinan 250022, China
| | - Xinyi Yuan
- School of Biological Science and Technology, University of Jinan, Jinan 250022, China
| | - Fenghua Wu
- School of Biological Science and Technology, University of Jinan, Jinan 250022, China
| | - Wenda Wang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Jian-Ren Shen
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Tingyun Kuang
- Photosynthesis Research Center, Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
| | - Xiaochun Qin
- School of Biological Science and Technology, University of Jinan, Jinan 250022, China
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3
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Hu C, Nawrocki WJ, Croce R. Long-term adaptation of Arabidopsis thaliana to far-red light. PLANT, CELL & ENVIRONMENT 2021; 44:3002-3014. [PMID: 33599977 PMCID: PMC8453498 DOI: 10.1111/pce.14032] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/16/2021] [Accepted: 02/16/2021] [Indexed: 05/04/2023]
Abstract
Vascular plants use carotenoids and chlorophylls a and b to harvest solar energy in the visible region (400-700 nm), but they make little use of the far-red (FR) light. Instead, some cyanobacteria have developed the ability to use FR light by redesigning their photosynthetic apparatus and synthesizing red-shifted chlorophylls. Implementing this strategy in plants is considered promising to increase crop yield. To prepare for this, a characterization of the FR light-induced changes in plants is necessary. Here, we explore the behaviour of Arabidopsis thaliana upon exposure to FR light by following the changes in morphology, physiology and composition of the photosynthetic complexes. We found that after FR-light treatment, the ratio between the photosystems and their antenna size drastically readjust in an attempt to rebalance the energy input to support electron transfer. Despite a large increase in PSBS accumulation, these adjustments result in strong photoinhibition when FR-adapted plants are exposed to light again. Crucially, FR light-induced changes in the photosynthetic membrane are not the result of senescence, but are a response to the excitation imbalance between the photosystems. This indicates that an increase in the FR absorption by the photosystems should be sufficient for boosting photosynthetic activity in FR light.
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Affiliation(s)
- Chen Hu
- Biophysics of Photosynthesis, Department of Physics and Astronomy, Faculty of ScienceVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Wojciech J. Nawrocki
- Biophysics of Photosynthesis, Department of Physics and Astronomy, Faculty of ScienceVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Roberta Croce
- Biophysics of Photosynthesis, Department of Physics and Astronomy, Faculty of ScienceVrije Universiteit AmsterdamAmsterdamThe Netherlands
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4
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Rantala M, Rantala S, Aro EM. Composition, phosphorylation and dynamic organization of photosynthetic protein complexes in plant thylakoid membrane. Photochem Photobiol Sci 2021; 19:604-619. [PMID: 32297616 DOI: 10.1039/d0pp00025f] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The photosystems (PS), catalyzing the photosynthetic reactions of higher plants, are unevenly distributed in the thylakoid membrane: PSII, together with its light harvesting complex (LHC)II, is enriched in the appressed grana stacks, while PSI-LHCI resides in the non-appressed stroma thylakoids, which wind around the grana stacks. The two photosystems interact in a third membrane domain, the grana margins, which connect the grana and stroma thylakoids and allow the loosely bound LHCII to serve as an additional antenna for PSI. The light harvesting is balanced by reversible phosphorylation of LHCII proteins. Nevertheless, light energy also damages PSII and the repair process is regulated by reversible phosphorylation of PSII core proteins. Here, we discuss the detailed composition and organization of PSII-LHCII and PSI-LHCI (super)complexes in the thylakoid membrane of angiosperm chloroplasts and address the role of thylakoid protein phosphorylation in dynamics of the entire protein complex network of the photosynthetic membrane. Finally, we scrutinize the phosphorylation-dependent dynamics of the protein complexes in context of thylakoid ultrastructure and present a model on the reorganization of the entire thylakoid network in response to changes in thylakoid protein phosphorylation.
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Affiliation(s)
- Marjaana Rantala
- Molecular Plant Biology, Department of Biochemistry, University of Turku, FI-20520, Turku, Finland
| | - Sanna Rantala
- Molecular Plant Biology, Department of Biochemistry, University of Turku, FI-20520, Turku, Finland
| | - Eva-Mari Aro
- Molecular Plant Biology, Department of Biochemistry, University of Turku, FI-20520, Turku, Finland.
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5
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Koskela MM, Brünje A, Ivanauskaite A, Lopez LS, Schneider D, DeTar RA, Kunz HH, Finkemeier I, Mulo P. Comparative analysis of thylakoid protein complexes in state transition mutants nsi and stn7: focus on PSI and LHCII. PHOTOSYNTHESIS RESEARCH 2020; 145:15-30. [PMID: 31975158 PMCID: PMC7308260 DOI: 10.1007/s11120-020-00711-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Accepted: 01/09/2020] [Indexed: 05/17/2023]
Abstract
The photosynthetic machinery of plants can acclimate to changes in light conditions by balancing light-harvesting between the two photosystems (PS). This acclimation response is induced by the change in the redox state of the plastoquinone pool, which triggers state transitions through activation of the STN7 kinase and subsequent phosphorylation of light-harvesting complex II (LHCII) proteins. Phosphorylation of LHCII results in its association with PSI (state 2), whereas dephosphorylation restores energy allocation to PSII (state 1). In addition to state transition regulation by phosphorylation, we have recently discovered that plants lacking the chloroplast acetyltransferase NSI are also locked in state 1, even though they possess normal LHCII phosphorylation. This defect may result from decreased lysine acetylation of several chloroplast proteins. Here, we compared the composition of wild type (wt), stn7 and nsi thylakoid protein complexes involved in state transitions separated by Blue Native gel electrophoresis. Protein complex composition and relative protein abundances were determined by LC-MS/MS analyses using iBAQ quantification. We show that despite obvious mechanistic differences leading to defects in state transitions, no major differences were detected in the composition of PSI and LHCII between the mutants. Moreover, both stn7 and nsi plants show retarded growth and decreased PSII capacity under fluctuating light as compared to wt, while the induction of non-photochemical quenching under fluctuating light was much lower in both nsi mutants than in stn7.
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Affiliation(s)
- Minna M Koskela
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Biocity A, Tykistökatu 6, 20520, Turku, Finland
- Centre Algatech, Institute of Microbiology, Czech Academy of Sciences, Novohradská 237 - Opatovický mlýn, 379 81, Třebon, Czech Republic
| | - Annika Brünje
- Plant Physiology, Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 7, 48149, Münster, Germany
| | - Aiste Ivanauskaite
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Biocity A, Tykistökatu 6, 20520, Turku, Finland
| | - Laura S Lopez
- Plant Physiology, School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA
| | - Dominik Schneider
- Compact Plants Phenomics Center, Washington State University, Pullman, WA, 99164, USA
- Institute of Biological Chemistry, Washington State University, Pullman, WA, 99164-6340, USA
| | - Rachael A DeTar
- Plant Physiology, School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA
| | - Hans-Henning Kunz
- Plant Physiology, School of Biological Sciences, Washington State University, Pullman, WA, 99164-4236, USA
| | - Iris Finkemeier
- Plant Physiology, Institute of Plant Biology and Biotechnology, University of Münster, Schlossplatz 7, 48149, Münster, Germany.
| | - Paula Mulo
- Department of Biochemistry, Molecular Plant Biology, University of Turku, Biocity A, Tykistökatu 6, 20520, Turku, Finland.
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Kouřil R, Nosek L, Semchonok D, Boekema EJ, Ilík P. Organization of Plant Photosystem II and Photosystem I Supercomplexes. Subcell Biochem 2018; 87:259-286. [PMID: 29464563 DOI: 10.1007/978-981-10-7757-9_9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
In nature, plants are continuously exposed to varying environmental conditions. They have developed a wide range of adaptive mechanisms, which ensure their survival and maintenance of stable photosynthetic performance. Photosynthesis is delicately regulated at the level of the thylakoid membrane of chloroplasts and the regulatory mechanisms include a reversible formation of a large variety of specific protein-protein complexes, supercomplexes or even larger assemblies known as megacomplexes. Revealing their structures is crucial for better understanding of their function and relevance in photosynthesis. Here we focus our attention on the isolation and a structural characterization of various large protein supercomplexes and megacomplexes, which involve Photosystem II and Photosystem I, the key constituents of photosynthetic apparatus. The photosystems are often attached to other protein complexes in thylakoid membranes such as light harvesting complexes, cytochrome b 6 f complex, and NAD(P)H dehydrogenase. Structural models of individual supercomplexes and megacomplexes provide essential details of their architecture, which allow us to discuss their function as well as physiological significance.
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Affiliation(s)
- Roman Kouřil
- Department of Biophysics, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Olomouc, Czech Republic.
| | - Lukáš Nosek
- Department of Biophysics, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Olomouc, Czech Republic
| | - Dmitry Semchonok
- Electron Microscopy Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Egbert J Boekema
- Electron Microscopy Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
| | - Petr Ilík
- Department of Biophysics, Faculty of Science, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Olomouc, Czech Republic
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7
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Marco P, Kozuleva M, Eilenberg H, Mazor Y, Gimeson P, Kanygin A, Redding K, Weiner I, Yacoby I. Binding of ferredoxin to algal photosystem I involves a single binding site and is composed of two thermodynamically distinct events. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:234-243. [DOI: 10.1016/j.bbabio.2018.01.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 01/07/2018] [Accepted: 01/08/2018] [Indexed: 10/18/2022]
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8
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Structure of the plant photosystem I. Biochem Soc Trans 2018; 46:285-294. [PMID: 29487228 DOI: 10.1042/bst20170299] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 01/16/2018] [Accepted: 01/22/2018] [Indexed: 11/17/2022]
Abstract
Plant photosystem I (PSI) is one of the most intricate membrane complexes in nature. It comprises two complexes, a reaction center and light-harvesting complex (LHC), which together form the PSI-LHC supercomplex. The crystal structure of plant PSI was solved with two distinct crystal forms. The first, crystallized at pH 6.5, exhibited P21 symmetry; the second, crystallized at pH 8.5, exhibited P212121 symmetry. The surfaces involved in binding plastocyanin and ferredoxin are identical in both forms. The crystal structure at 2.6 Å resolution revealed 16 subunits, 45 transmembrane helices, and 232 prosthetic groups, including 143 chlorophyll a, 13 chlorophyll b, 27 β-carotene, 7 lutein, 2 xanthophyll, 1 zeaxanthin, 20 monogalactosyl diglyceride, 7 phosphatidyl diglyceride, 5 digalactosyl diglyceride, 2 calcium ions, 2 phylloquinone, and 3 iron sulfur clusters. The model reveals detailed interactions, providing mechanisms for excitation energy transfer and its modulation in one of nature's most efficient photochemical machine.
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9
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Iwai M, Yokono M. Light-harvesting antenna complexes in the moss Physcomitrella patens: implications for the evolutionary transition from green algae to land plants. CURRENT OPINION IN PLANT BIOLOGY 2017; 37:94-101. [PMID: 28445834 DOI: 10.1016/j.pbi.2017.04.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 04/03/2017] [Accepted: 04/05/2017] [Indexed: 05/10/2023]
Abstract
Plants have successfully adapted to a vast range of terrestrial environments during their evolution. To elucidate the evolutionary transition of light-harvesting antenna proteins from green algae to land plants, the moss Physcomitrella patens is ideally placed basally among land plants. Compared to the genomes of green algae and land plants, the P. patens genome codes for more diverse and redundant light-harvesting antenna proteins. It also encodes Lhcb9, which has characteristics not found in other light-harvesting antenna proteins. The unique complement of light-harvesting antenna proteins in P. patens appears to facilitate protein interactions that include those lost in both green algae and land plants with regard to stromal electron transport pathways and photoprotection mechanisms. This review will highlight unique characteristics of the P. patens light-harvesting antenna system and the resulting implications about the evolutionary transition during plant terrestrialization.
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Affiliation(s)
- Masakazu Iwai
- Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720-3102, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Makio Yokono
- Institute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan
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10
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Bína D, Gardian Z, Herbstová M, Litvín R. Modular antenna of photosystem I in secondary plastids of red algal origin: a Nannochloropsis oceanica case study. PHOTOSYNTHESIS RESEARCH 2017; 131:255-266. [PMID: 27734239 DOI: 10.1007/s11120-016-0315-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 10/05/2016] [Indexed: 06/06/2023]
Abstract
Photosystem I (PSI) is a multi-subunit integral pigment-protein complex that performs light-driven electron transfer from plastocyanin to ferredoxin in the thylakoid membrane of oxygenic photoautotrophs. In order to achieve the optimal photosynthetic performance under ambient irradiance, the absorption cross section of PSI is extended by means of peripheral antenna complexes. In eukaryotes, this role is played mostly by the pigment-protein complexes of the LHC family. The structure of the PSI-antenna supercomplexes has been relatively well understood in organisms harboring the primary plastid: red algae, green algae and plants. The secondary endosymbiotic algae, despite their major ecological importance, have so far received less attention. Here we report a detailed structural analysis of the antenna-PSI association in the stramenopile alga Nannochloropsis oceanica (Eustigmatophyceae). Several types of PSI-antenna assemblies are identified allowing for identification of antenna docking sites on the PSI core. Instances of departure of the stramenopile system from the red algal model of PSI-Lhcr structure are recorded, and evolutionary implications of these observations are discussed.
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Affiliation(s)
- David Bína
- Institute of Plant Molecular Biology, Biology Centre CAS, Branišovská 31, 370 05, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05, České Budějovice, Czech Republic
| | - Zdenko Gardian
- Institute of Plant Molecular Biology, Biology Centre CAS, Branišovská 31, 370 05, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05, České Budějovice, Czech Republic
| | - Miroslava Herbstová
- Institute of Plant Molecular Biology, Biology Centre CAS, Branišovská 31, 370 05, České Budějovice, Czech Republic
- Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05, České Budějovice, Czech Republic
| | - Radek Litvín
- Institute of Plant Molecular Biology, Biology Centre CAS, Branišovská 31, 370 05, České Budějovice, Czech Republic.
- Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05, České Budějovice, Czech Republic.
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11
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High photochemical trapping efficiency in Photosystem I from the red clade algae Chromera velia and Phaeodactylum tricornutum. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2017; 1858:56-63. [DOI: 10.1016/j.bbabio.2016.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/06/2016] [Accepted: 10/07/2016] [Indexed: 11/23/2022]
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12
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Ruban AV, Johnson MP. Visualizing the dynamic structure of the plant photosynthetic membrane. NATURE PLANTS 2015; 1:15161. [PMID: 27251532 DOI: 10.1038/nplants.2015.161] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Accepted: 09/29/2015] [Indexed: 05/28/2023]
Abstract
The chloroplast thylakoid membrane is the site for the initial steps of photosynthesis that convert solar energy into chemical energy, ultimately powering almost all life on earth. The heterogeneous distribution of protein complexes within the membrane gives rise to an intricate three-dimensional structure that is nonetheless extremely dynamic on a timescale of seconds to minutes. These dynamics form the basis for the regulation of photosynthesis, and therefore the adaptability of plants to different environments. High-resolution microscopy has in recent years begun to provide new insights into the structural dynamics underlying a number of regulatory processes such as membrane stacking, photosystem II repair, photoprotective energy dissipation, state transitions and alternative electron transfer. Here we provide an overview of the essentials of thylakoid membrane structure in plants, and consider how recent advances, using a range of microscopies, have substantially increased our knowledge of the thylakoid dynamic structure. We discuss both the successes and limitations of the currently available techniques and highlight newly emerging microscopic methods that promise to move the field beyond the current 'static' view of membrane organization based on frozen snapshots to a 'live' view of functional membranes imaged under native aqueous conditions at ambient temperature and responding dynamically to external stimuli.
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Affiliation(s)
- Alexander V Ruban
- School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, UK
| | - Matthew P Johnson
- Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK
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13
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Le Quiniou C, Tian L, Drop B, Wientjes E, van Stokkum IHM, van Oort B, Croce R. PSI-LHCI of Chlamydomonas reinhardtii: Increasing the absorption cross section without losing efficiency. BIOCHIMICA ET BIOPHYSICA ACTA 2015; 1847:458-467. [PMID: 25681242 PMCID: PMC4547092 DOI: 10.1016/j.bbabio.2015.02.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 01/28/2015] [Accepted: 02/02/2015] [Indexed: 11/28/2022]
Abstract
Photosystem I (PSI) is an essential component of photosynthetic membranes. Despite the high sequence and structural homologies, its absorption properties differ substantially in algae, plants and cyanobacteria. In particular it is characterized by the presence of low-energy chlorophylls (red forms), the number and the energy of which vary in different organisms. The PSI-LHCI (PSI-light harvesting complex I) complex of the green alga Chlamydomonas reinhardtii (C.r.) is significantly larger than that of plants, containing five additional light-harvesting complexes (together binding≈65 chlorophylls), and contains red forms with higher energy than plants. To understand how these differences influence excitation energy transfer and trapping in the system, we studied two PSI-LHCI C.r. particles, differing in antenna size and red-form content, using time-resolved fluorescence and compared them to plant PSI-LHCI. The excited state kinetics in C.r. shows the same average lifetime (50 ps) as in plants suggesting that the effect of antenna enlargement is compensated by higher energy red forms. The system equilibrates very fast, indicating that all Lhcas are well-connected, despite their long distance to the core. The differences between C.r. PSI-LHCI with and without Lhca2 and Lhca9 show that these Lhcas bind red forms, although not the red-most. The red-most forms are in (or functionally close to) other Lhcas and slow down the trapping, but hardly affect the quantum efficiency, which remains as high as 97% even in a complex that contains 235 chlorophylls.
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Affiliation(s)
- Clotilde Le Quiniou
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Institute for Lasers, Life and Biophotonics Amsterdam, LaserLaB Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Lijin Tian
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Institute for Lasers, Life and Biophotonics Amsterdam, LaserLaB Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Bartlomiej Drop
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Institute for Lasers, Life and Biophotonics Amsterdam, LaserLaB Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Emilie Wientjes
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Institute for Lasers, Life and Biophotonics Amsterdam, LaserLaB Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Ivo H M van Stokkum
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Institute for Lasers, Life and Biophotonics Amsterdam, LaserLaB Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Bart van Oort
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Institute for Lasers, Life and Biophotonics Amsterdam, LaserLaB Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Roberta Croce
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Institute for Lasers, Life and Biophotonics Amsterdam, LaserLaB Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
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14
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Abstract
Oxygenic photosynthesis is the principal converter of sunlight into chemical energy on Earth. Cyanobacteria and plants provide the oxygen, food, fuel, fibers, and platform chemicals for life on Earth. The conversion of solar energy into chemical energy is catalyzed by two multisubunit membrane protein complexes, photosystem I (PSI) and photosystem II (PSII). Light is absorbed by the pigment cofactors, and excitation energy is transferred among the antennae pigments and converted into chemical energy at very high efficiency. Oxygenic photosynthesis has existed for more than three billion years, during which its molecular machinery was perfected to minimize wasteful reactions. Light excitation transfer and singlet trapping won over fluorescence, radiation-less decay, and triplet formation. Photosynthetic reaction centers operate in organisms ranging from bacteria to higher plants. They are all evolutionarily linked. The crystal structure determination of photosynthetic protein complexes sheds light on the various partial reactions and explains how they are protected against wasteful pathways and why their function is robust. This review discusses the efficiency of photosynthetic solar energy conversion.
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Affiliation(s)
- Nathan Nelson
- Department of Biochemistry, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel;
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15
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Nelson CJ, Millar AH. Protein turnover in plant biology. NATURE PLANTS 2015; 1:15176. [PMID: 27246884 DOI: 10.1038/nplants.2015.176] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 10/14/2015] [Indexed: 05/20/2023]
Abstract
The protein content of plant cells is constantly being updated. This process is driven by the opposing actions of protein degradation, which defines the half-life of each polypeptide, and protein synthesis. Our understanding of the processes that regulate protein synthesis and degradation in plants has advanced significantly over the past decade. Post-transcriptional modifications that influence features of the mRNA populations, such as poly(A) tail length and secondary structure, contribute to the regulation of protein synthesis. Post-translational modifications such as phosphorylation, ubiquitination and non-enzymatic processes such as nitrosylation and carbonylation, govern the rate of degradation. Regulators such as the plant TOR kinase, and effectors such as the E3 ligases, allow plants to balance protein synthesis and degradation under developmental and environmental change. Establishing an integrated understanding of the processes that underpin changes in protein abundance under various physiological and developmental scenarios will accelerate our ability to model and rationally engineer plants.
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Affiliation(s)
- Clark J Nelson
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Hwy, Crawley 6009, Perth, Western Australia, Australia
| | - A Harvey Millar
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Hwy, Crawley 6009, Perth, Western Australia, Australia
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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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17
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Karapetyan NV, Bolychevtseva YV, Yurina NP, Terekhova IV, Shubin VV, Brecht M. Long-wavelength chlorophylls in photosystem I of cyanobacteria: origin, localization, and functions. BIOCHEMISTRY (MOSCOW) 2014; 79:213-20. [PMID: 24821447 DOI: 10.1134/s0006297914030067] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The structural organization of photosystem I (PSI) complexes in cyanobacteria and the origin of the PSI antenna long-wavelength chlorophylls and their role in energy migration, charge separation, and dissipation of excess absorbed energy are discussed. The PSI complex in cyanobacterial membranes is organized preferentially as a trimer with the core antenna enriched with long-wavelength chlorophylls. The contents of long-wavelength chlorophylls and their spectral characteristics in PSI trimers and monomers are species-specific. Chlorophyll aggregates in PSI antenna are potential candidates for the role of the long-wavelength chlorophylls. The red-most chlorophylls in PSI trimers of the cyanobacteria Arthrospira platensis and Thermosynechococcus elongatus can be formed as a result of interaction of pigments peripherally localized on different monomeric complexes within the PSI trimers. Long-wavelength chlorophylls affect weakly energy equilibration within the heterogeneous PSI antenna, but they significantly delay energy trapping by P700. When the reaction center is open, energy absorbed by long-wavelength chlorophylls migrates to P700 at physiological temperatures, causing its oxidation. When the PSI reaction center is closed, the P700 cation radical or P700 triplet state (depending on the P700 redox state and the PSI acceptor side cofactors) efficiently quench the fluorescence of the long-wavelength chlorophylls of PSI and thus protect the complex against photodestruction.
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Affiliation(s)
- N V Karapetyan
- Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, 119071, Russia.
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18
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Schlodder E, Lendzian F, Meyer J, Çetin M, Brecht M, Renger T, Karapetyan N. Long-wavelength limit of photochemical energy conversion in Photosystem I. J Am Chem Soc 2014; 136:3904-18. [PMID: 24517238 PMCID: PMC3959156 DOI: 10.1021/ja412375j] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Indexed: 11/30/2022]
Abstract
In Photosystem I (PS I) long-wavelength chlorophylls (LWC) of the core antenna are known to extend the spectral region up to 750 nm for absorbance of light that drives photochemistry. Here we present clear evidence that even far-red light with wavelengths beyond 800 nm, clearly outside the LWC absorption bands, can still induce photochemical charge separation in PS I throughout the full temperature range from 295 to 5 K. At room temperature, the photoaccumulation of P700(+•) was followed by the absorbance increase at 826 nm. At low temperatures (T < 100 K), the formation of P700(+•)FA/B(-•) was monitored by the characteristic EPR signals of P700(+•) and FA/B(-•) and by the characteristic light-minus-dark absorbance difference spectrum in the QY region. P700 oxidation was observed upon selective excitation at 754, 785, and 808 nm, using monomeric and trimeric PS I core complexes of Thermosynechococcus elongatus and Arthrospira platensis, which differ in the amount of LWC. The results show that the LWC cannot be responsible for the long-wavelength excitation-induced charge separation at low temperatures, where thermal uphill energy transfer is frozen out. Direct energy conversion of the excitation energy from the LWC to the primary radical pair, e.g., via a superexchange mechanism, is excluded, because no dependence on the content of LWC was observed. Therefore, it is concluded that electron transfer through PS I is induced by direct excitation of a proposed charge transfer (CT) state in the reaction center. A direct signature of this CT state is seen in absorbance spectra of concentrated PS I samples, which reveal a weak and featureless absorbance band extending beyond 800 nm, in addition to the well-known bands of LWC (C708, C719 and C740) in the range between 700 and 750 nm. The present findings suggest that nature can exploit CT states for extending the long wavelength limit in PSI even beyond that of LWC. Similar mechanisms may work in other photosynthetic systems and in chemical systems capable of photoinduced electron transfer processes in general.
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Affiliation(s)
- Eberhard Schlodder
- Max-Volmer-Laboratorium für Biophysikalische Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany
| | - Friedhelm Lendzian
- Max-Volmer-Laboratorium für Biophysikalische Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany
| | - Jenny Meyer
- Max-Volmer-Laboratorium für Biophysikalische Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany
| | - Marianne Çetin
- Max-Volmer-Laboratorium für Biophysikalische Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany
| | - Marc Brecht
- Institut für
Physikalische und Theoretische Physik, Eberhard-Karls-Universität
Tübingen, Auf
der Morgenstelle 14, 71976 Tübingen, Germany
| | - Thomas Renger
- Institut
für Theoretische Physik, Johannes
Kepler Universität, Abteilung Theoretische
Biophysik, Altenberger
Str. 69, Linz, Austria
| | - Navasard
V. Karapetyan
- A.N. Bach Institute of Biochemistry, Russian Academy of Sciences, Leninsky Prospect 33, 119071 Moscow, Russia
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Alterations in Structural Organization Affect the Functional Ability of Photosynthetic Apparatus. ACTA ACUST UNITED AC 2014. [DOI: 10.1201/b16675-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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20
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Basso S, Simionato D, Gerotto C, Segalla A, Giacometti GM, Morosinotto T. Characterization of the photosynthetic apparatus of the Eustigmatophycean Nannochloropsis gaditana: Evidence of convergent evolution in the supramolecular organization of photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1837:306-14. [DOI: 10.1016/j.bbabio.2013.11.019] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 11/18/2013] [Accepted: 11/24/2013] [Indexed: 12/11/2022]
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21
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Minagawa J. Dynamic reorganization of photosynthetic supercomplexes during environmental acclimation of photosynthesis. FRONTIERS IN PLANT SCIENCE 2013; 4:513. [PMID: 24381578 PMCID: PMC3865443 DOI: 10.3389/fpls.2013.00513] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Accepted: 11/30/2013] [Indexed: 05/18/2023]
Abstract
Plants and algae have acquired the ability to acclimate to ever-changing environments in order to survive. During photosynthesis, light energy is converted by several membrane protein supercomplexes into electrochemical energy, which is eventually used to assimilate CO2. The efficiency of photosynthesis is modulated by many environmental factors such as quality and quantity of light, temperature, drought, and CO2 concentration, among others. Accumulating evidence indicates that photosynthetic supercomplexes undergo supramolecular reorganization within a short time frame during acclimation to an environmental change. This reorganization includes state transitions that balance the excitation of photosystem I and II by shuttling peripheral antenna proteins between the two, thermal energy dissipation that occurs at energy-quenching sites within the light-harvesting antenna generated for negative feedback when excess light is absorbed, and cyclic electron flow that is facilitated between photosystem I and the cytochrome bf complex when cells demand more ATP and/or need to activate energy dissipation. This review will highlight the recent findings regarding these environmental acclimation events in model organisms with particular attention to the unicellular green alga C. reinhardtii and with reference to the vascular plant A. thaliana, which offers a glimpse into the dynamic behavior of photosynthetic machineries in nature.
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Affiliation(s)
- Jun Minagawa
- *Correspondence: Jun Minagawa, Division of Environmental Photobiology, National Institute for Basic Biology, 38 Nishigonaka, Okazaki 444-8585, Japan e-mail:
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22
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Croce R, van Amerongen H. Light-harvesting in photosystem I. PHOTOSYNTHESIS RESEARCH 2013; 116:153-66. [PMID: 23645376 PMCID: PMC3825136 DOI: 10.1007/s11120-013-9838-x] [Citation(s) in RCA: 169] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 04/23/2013] [Indexed: 05/18/2023]
Abstract
This review focuses on the light-harvesting properties of photosystem I (PSI) and its LHCI outer antenna. LHCI consists of different chlorophyll a/b binding proteins called Lhca's, surrounding the core of PSI. In total, the PSI-LHCI complex of higher plants contains 173 chlorophyll molecules, most of which are there to harvest sunlight energy and to transfer the created excitation energy to the reaction center (RC) where it is used for charge separation. The efficiency of the complex is based on the capacity to deliver this energy to the RC as fast as possible, to minimize energy losses. The performance of PSI in this respect is remarkable: on average it takes around 50 ps for the excitation to reach the RC in plants, without being quenched in the meantime. This means that the internal quantum efficiency is close to 100% which makes PSI the most efficient energy converter in nature. In this review, we describe the light-harvesting properties of the complex in relation to protein and pigment organization/composition, and we discuss the important parameters that assure its very high quantum efficiency. Excitation energy transfer and trapping in the core and/or Lhcas, as well as in the supercomplexes PSI-LHCI and PSI-LHCI-LHCII are described in detail with the aim of giving an overview of the functional behavior of these complexes.
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Affiliation(s)
- Roberta Croce
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands,
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23
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Busch A, Petersen J, Webber-Birungi MT, Powikrowska M, Lassen LMM, Naumann-Busch B, Nielsen AZ, Ye J, Boekema EJ, Jensen ON, Lunde C, Jensen PE. Composition and structure of photosystem I in the moss Physcomitrella patens. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:2689-99. [PMID: 23682117 PMCID: PMC3697952 DOI: 10.1093/jxb/ert126] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Recently, bryophytes, which diverged from the ancestor of seed plants more than 400 million years ago, came into focus in photosynthesis research as they can provide valuable insights into the evolution of photosynthetic complexes during the adaptation to terrestrial life. This study isolated intact photosystem I (PSI) with its associated light-harvesting complex (LHCI) from the moss Physcomitrella patens and characterized its structure, polypeptide composition, and light-harvesting function using electron microscopy, mass spectrometry, biochemical, and physiological methods. It became evident that Physcomitrella possesses a strikingly high number of isoforms for the different PSI core subunits as well as LHCI proteins. It was demonstrated that all these different subunit isoforms are expressed at the protein level and are incorporated into functional PSI-LHCI complexes. Furthermore, in contrast to previous reports, it was demonstrated that Physcomitrella assembles a light-harvesting complex consisting of four light-harvesting proteins forming a higher-plant-like PSI superstructure.
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Affiliation(s)
- Andreas Busch
- VKR Research Centre ‘Pro-Active Plants’ and Center for Synthetic Biology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Jørgen Petersen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Mariam T. Webber-Birungi
- Electron Microscopy Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Marta Powikrowska
- VKR Research Centre ‘Pro-Active Plants’ and Center for Synthetic Biology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Lærke Marie Münter Lassen
- VKR Research Centre ‘Pro-Active Plants’ and Center for Synthetic Biology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Bianca Naumann-Busch
- VKR Research Centre ‘Pro-Active Plants’ and Center for Synthetic Biology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Agnieszka Zygadlo Nielsen
- VKR Research Centre ‘Pro-Active Plants’ and Center for Synthetic Biology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Juanying Ye
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Egbert J. Boekema
- Electron Microscopy Group, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Ole Nørregaard Jensen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Christina Lunde
- VKR Research Centre ‘Pro-Active Plants’ and Center for Synthetic Biology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
| | - Poul Erik Jensen
- VKR Research Centre ‘Pro-Active Plants’ and Center for Synthetic Biology, Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C, Denmark
- *To whom correspondence should be addressed.
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24
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Photochemical trapping heterogeneity as a function of wavelength, in plant photosystem I (PSI–LHCI). BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:779-85. [DOI: 10.1016/j.bbabio.2013.03.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 03/12/2013] [Accepted: 03/20/2013] [Indexed: 11/18/2022]
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25
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LHCII is an antenna of both photosystems after long-term acclimation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:420-6. [DOI: 10.1016/j.bbabio.2012.12.009] [Citation(s) in RCA: 173] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Revised: 11/25/2012] [Accepted: 12/27/2012] [Indexed: 11/17/2022]
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26
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Light harvesting complexes of Chromera velia, photosynthetic relative of apicomplexan parasites. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:723-9. [PMID: 23428396 DOI: 10.1016/j.bbabio.2013.02.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Revised: 01/31/2013] [Accepted: 02/05/2013] [Indexed: 01/24/2023]
Abstract
The structure and composition of the light harvesting complexes from the unicellular alga Chromera velia were studied by means of optical spectroscopy, biochemical and electron microscopy methods. Two different types of antennae systems were identified. One exhibited a molecular weight (18-19kDa) similar to FCP (fucoxanthin chlorophyll protein) complexes from diatoms, however, single particle analysis and circular dichroism spectroscopy indicated similarity of this structure to the recently characterized XLH antenna of xanthophytes. In light of these data we denote this antenna complex CLH, for "Chromera Light Harvesting" complex. The other system was identified as the photosystem I with bound Light Harvesting Complexes (PSI-LHCr) related to the red algae LHCI antennae. The result of this study is the finding that C. velia, when grown in natural light conditions, possesses light harvesting antennae typically found in two different, evolutionary distant, groups of photosynthetic organisms.
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27
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Nevo R, Charuvi D, Tsabari O, Reich Z. Composition, architecture and dynamics of the photosynthetic apparatus in higher plants. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 70:157-76. [PMID: 22449050 DOI: 10.1111/j.1365-313x.2011.04876.x] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The process of oxygenic photosynthesis enabled and still sustains aerobic life on Earth. The most elaborate form of the apparatus that carries out the primary steps of this vital process is the one present in higher plants. Here, we review the overall composition and supramolecular organization of this apparatus, as well as the complex architecture of the lamellar system within which it is harbored. Along the way, we refer to the genetic, biochemical, spectroscopic and, in particular, microscopic studies that have been employed to elucidate the structure and working of this remarkable molecular energy conversion device. As an example of the highly dynamic nature of the apparatus, we discuss the molecular and structural events that enable it to maintain high photosynthetic yields under fluctuating light conditions. We conclude the review with a summary of the hypotheses made over the years about the driving forces that underlie the partition of the lamellar system of higher plants and certain green algae into appressed and non-appressed membrane domains and the segregation of the photosynthetic protein complexes within these domains.
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Affiliation(s)
- Reinat Nevo
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot, Israel
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28
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Wientjes E, Croce R. PMS: photosystem I electron donor or fluorescence quencher. PHOTOSYNTHESIS RESEARCH 2012; 111:185-91. [PMID: 21879310 PMCID: PMC3296009 DOI: 10.1007/s11120-011-9671-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Accepted: 07/07/2011] [Indexed: 05/18/2023]
Abstract
Light energy harvested by the pigments in Photosystem I (PSI) is used for charge separation in the reaction center (RC), after which the positive charge resides on a special chlorophyll dimer called P700. In studies on the PSI trapping kinetics, P700(+) is usually chemically reduced to re-open the RCs. So far, the information available about the reduction rate and possible chlorophyll fluorescence quenching effects of these reducing agents is limited. This information is indispensible to estimate the fraction of open RCs under known experimental conditions. Moreover, it would be important to understand if these reagents have a chlorophyll fluorescence quenching effects to avoid the introduction of exogenous singlet excitation quenching in the measurements. In this study, we investigated the effect of the commonly used reducing agent phenazine methosulfate (PMS) on the RC and fluorescence emission of higher plant PSI-LHCI. We measured the P700(+) reduction rate for different PMS concentrations, and show that we can give a reliable estimation on the fraction of closed RCs based on these rates. The data show that PMS is quenching chlorophyll fluorescence emission. Finally, we determined that the fluorescence quantum yield of PSI with closed RCs is 4% higher than if the RCs are open.
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Affiliation(s)
- Emilie Wientjes
- Department of Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands.
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29
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Collins AM, Wen J, Blankenship RE. Photosynthetic Light-Harvesting Complexes. MOLECULAR SOLAR FUELS 2011. [DOI: 10.1039/9781849733038-00085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The light-harvesting antenna systems found in photosynthetic organisms function to collect light and transfer energy in the photon to a reaction center, where electron transfer gives rise to long-term energy storage. The antenna systems found in different types of photosynthetic organisms adapt the organisms to very different photic environments, and almost certainly have been invented multiple times during evolution. The diverse collection of photosynthetic antenna systems is described in terms of their pigment and protein components and their organization in the photosystem. The Förster theory is described as the physical basis of energy transfer in photosynthetic antennas, although in many systems it is not adequate to describe energy transfer in complexes with closely interacting pigments. Regulatory aspects of antennas are described, including the process of non-photochemical quenching.
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Affiliation(s)
- Aaron M. Collins
- Departments of Biology and Chemistry Washington University in St. Louis, St. Louis, MO 63130 USA
| | - Jianzhong Wen
- Departments of Biology and Chemistry Washington University in St. Louis, St. Louis, MO 63130 USA
| | - Robert E. Blankenship
- Departments of Biology and Chemistry Washington University in St. Louis, St. Louis, MO 63130 USA
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30
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The role of the individual Lhcas in photosystem I excitation energy trapping. Biophys J 2011; 101:745-54. [PMID: 21806943 DOI: 10.1016/j.bpj.2011.06.045] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 06/22/2011] [Accepted: 06/24/2011] [Indexed: 11/20/2022] Open
Abstract
In this work, we have investigated the role of the individual antenna complexes and of the low-energy forms in excitation energy transfer and trapping in Photosystem I of higher plants. To this aim, a series of Photosystem I (sub)complexes with different antenna size/composition/absorption have been studied by picosecond fluorescence spectroscopy. The data show that Lhca3 and Lhca4, which harbor the most red forms, have similar emission spectra (λ(max) = 715-720 nm) and transfer excitation energy to the core with a relative slow rate of ∼25/ns. Differently, the energy transfer from Lhca1 and Lhca2, the "blue" antenna complexes, occurs about four times faster. In contrast to what is often assumed, it is shown that energy transfer from the Lhca1/4 and the Lhca2/3 dimer to the core occurs on a faster timescale than energy equilibration within these dimers. Furthermore, it is shown that all four monomers contribute almost equally to the transfer to the core and that the red forms slow down the overall trapping rate by about two times. Combining all the data allows the construction of a comprehensive picture of the excitation-energy transfer routes and rates in Photosystem I.
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31
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Schlodder E, Hussels M, Çetin M, Karapetyan NV, Brecht M. Fluorescence of the various red antenna states in photosystem I complexes from cyanobacteria is affected differently by the redox state of P700. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2011; 1807:1423-31. [DOI: 10.1016/j.bbabio.2011.06.018] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Revised: 06/27/2011] [Accepted: 06/29/2011] [Indexed: 11/30/2022]
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33
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Wientjes E, van Stokkum IHM, van Amerongen H, Croce R. Excitation-energy transfer dynamics of higher plant photosystem I light-harvesting complexes. Biophys J 2011; 100:1372-80. [PMID: 21354411 DOI: 10.1016/j.bpj.2011.01.030] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 01/19/2011] [Indexed: 11/15/2022] Open
Abstract
Photosystem I (PSI) plays a major role in the light reactions of photosynthesis. In higher plants, PSI is composed of a core complex and four outer antennas that are assembled as two dimers, Lhca1/4 and Lhca2/3. Time-resolved fluorescence measurements on the isolated dimers show very similar kinetics. The intermonomer transfer processes are resolved using target analysis. They occur at rates similar to those observed in transfer to the PSI core, suggesting competition between the two transfer pathways. It appears that each dimer is adopting various conformations that correspond to different lifetimes and emission spectra. A special feature of the Lhca complexes is the presence of an absorption band at low energy, originating from an excitonic state of a chlorophyll dimer, mixed with a charge-transfer state. These low-energy bands have high oscillator strengths and they are superradiant in both Lhca1/4 and Lhca2/3. This challenges the view that the low-energy charge-transfer state always functions as a quencher in plant Lhc's and it also challenges previous interpretations of PSI kinetics. The very similar properties of the low-energy states of both dimers indicate that the organization of the involved chlorophylls should also be similar, in disagreement with the available structural data.
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Affiliation(s)
- Emilie Wientjes
- Department of Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
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Thangaraj B, Jolley CC, Sarrou I, Bultema JB, Greyslak J, Whitelegge JP, Lin S, Kouřil R, Subramanyam R, Boekema EJ, Fromme P. Efficient light harvesting in a dark, hot, acidic environment: the structure and function of PSI-LHCI from Galdieria sulphuraria. Biophys J 2011; 100:135-43. [PMID: 21190665 DOI: 10.1016/j.bpj.2010.09.069] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 09/21/2010] [Accepted: 09/22/2010] [Indexed: 10/18/2022] Open
Abstract
Photosystem I-light harvesting complex I (PSI-LHCI) was isolated from the thermoacidophilic red alga Galdieria sulphuraria, and its structure, composition, and light-harvesting function were characterized by electron microscopy, mass spectrometry, and ultrafast optical spectroscopy. The results show that Galdieria PSI is a monomer with core features similar to those of PSI from green algae, but with significant differences in shape and size. A comparison with the crystal structure of higher plant (pea) PSI-LHCI indicates that Galdieria PSI binds seven to nine light-harvesting proteins. Results from ultrafast optical spectroscopy show that the functional coupling of the LHCI proteins to the PSI core is tighter than in other eukaryotic PSI-LHCI systems reported thus far. This tight coupling helps Galdieria perform efficient light harvesting under the low-light conditions present in its natural endolithic habitat.
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Affiliation(s)
- Balakumar Thangaraj
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona, USA
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The light-harvesting complexes of higher-plant Photosystem I: Lhca1/4 and Lhca2/3 form two red-emitting heterodimers. Biochem J 2011; 433:477-85. [PMID: 21083539 DOI: 10.1042/bj20101538] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The outer antenna of higher-plant PSI (Photosystem I) is composed of four complexes [Lhc (light-harvesting complex) a1-Lhca4] belonging to the light-harvesting protein family. Difficulties in their purification have so far prevented the determination of their properties and most of the knowledge about Lhcas has been obtained from the study of the in vitro reconstituted antennas. In the present study we were able to purify the native complexes, showing that Lhca2/3 and Lhca1/4 form two functional heterodimers. Both dimers show red-fluorescence emission with maxima around 730 nm, as in the intact PSI complex. This indicates that the dimers are in their native state and that LHCI-680, which was previously assumed to be part of the PSI antenna, does not represent the native state of the system. The data show that the light-harvesting properties of the two dimers are functionally identical, concerning absorption, long-wavelength emission and fluorescence quantum yield, whereas they differ in their high-light response. Implications of the present study for the understanding of the energy transfer process in PSI are discussed. Finally, the comparison of the properties of the native dimers with those of the reconstituted complexes demonstrates that all of the major properties of the Lhcas are reproduced in the in vitro systems.
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Minagawa J. State transitions--the molecular remodeling of photosynthetic supercomplexes that controls energy flow in the chloroplast. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1807:897-905. [PMID: 21108925 DOI: 10.1016/j.bbabio.2010.11.005] [Citation(s) in RCA: 165] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2010] [Revised: 11/08/2010] [Accepted: 11/10/2010] [Indexed: 11/29/2022]
Abstract
In oxygen-evolving photosynthesis, the two photosystems-photosystem I and photosystem II-function in parallel, and their excitation levels must be balanced to maintain an optimal photosynthetic rate under natural light conditions. State transitions in photosynthetic organisms balance the absorbed light energy between the two photosystems in a short time by relocating light-harvesting complex II proteins. For over a decade, the understanding of the physiological consequences, the molecular mechanism, and its regulation has increased considerably. After providing an overview of the general understanding of state transitions, this review focuses on the recent advances of the molecular aspects of state transitions with a particular emphasis on the studies using the green alga Chlamydomonas reinhardtii. This article is part of a Special Issue entitled: Regulation of Electron Transport in Chloroplasts.
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Affiliation(s)
- Jun Minagawa
- Nattional Institute for Basic Biology, Okazaki, Japan.
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El-Mohsnawy E, Kopczak MJ, Schlodder E, Nowaczyk M, Meyer HE, Warscheid B, Karapetyan NV, Rögner M. Structure and function of intact photosystem 1 monomers from the cyanobacterium Thermosynechococcus elongatus. Biochemistry 2010; 49:4740-51. [PMID: 20359245 DOI: 10.1021/bi901807p] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Until now, the functional and structural characterization of monomeric photosystem 1 (PS1) complexes from Thermosynechococcus elongatus has been hampered by the lack of a fully intact PS1 preparation; for this reason, the three-dimensional crystal structure at 2.5 A resolution was determined with the trimeric PS1 complex [Jordan, P., et al. (2001) Nature 411 (6840), 909-917]. Here we show the possibility of isolating from this cyanobacterium the intact monomeric PS1 complex which preserves all subunits and the photochemical activity of the isolated trimeric complex. Moreover, the equilibrium between these complexes in the thylakoid membrane can be shifted by a high-salt treatment in favor of monomeric PS1 which can be quantitatively extracted below the phase transition temperature. Both monomers and trimers exhibit identical posttranslational modifications of their subunits and the same reaction centers but differ in the long-wavelength antenna chlorophylls. Their chlorophyll/P700 ratio (108 for the monomer and 112 for the trimer) is slightly higher than in the crystal structure, confirming mild preparation conditions. Interaction of antenna chlorophylls of the monomers within the trimer leads to a larger amount of long-wavelength chlorophylls, resulting in a higher photochemical activity of the trimers under red or far-red illumination. The dynamic equilibrium between monomers and trimers in the thylakoid membrane may indicate a transient monomer population in the course of biogenesis and could also be the basis for short-term adaptation of the cell to changing environmental conditions.
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Amunts A, Nelson N. Plant Photosystem I Design in the Light of Evolution. Structure 2009; 17:637-50. [DOI: 10.1016/j.str.2009.03.006] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Revised: 03/23/2009] [Accepted: 03/25/2009] [Indexed: 11/26/2022]
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Wientjes E, Oostergetel GT, Jansson S, Boekema EJ, Croce R. The role of Lhca complexes in the supramolecular organization of higher plant photosystem I. J Biol Chem 2009; 284:7803-10. [PMID: 19139095 DOI: 10.1074/jbc.m808395200] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In this work, Photosystem I supercomplexes have been purified from Lhca-deficient lines of Arabidopsis thaliana using a mild detergent treatment that does not induce loss of outer antennas. The complexes have been studied by integrating biochemical analysis with electron microscopy. This allows the direct correlation of changes in protein content with changes in supramolecular structure of Photosystem I to get information about the position of the individual Lhca subunits, the association of the antenna to the core, and the influence of the individual subunits on the stability of the system. Photosystem I complexes with only two or three antenna complexes were purified, showing that the binding of Lhca1/4 and Lhca2/3 dimers to the core is not interdependent, although weak binding of Lhca2/3 to the core is stabilized by the presence of Lhca4. Moreover, Lhca2 and Lhca4 can be associated with the core in the absence of their "dimeric partners." The structure of Photosystem I is very rigid, and the absence of one antenna complex leaves a "hole" in the structure that cannot be filled by other Lhcas, clearly indicating that the docking sites for the individual subunits are highly specific. There is, however, an exception to the rule: Lhca5 can substitute for Lhca4, yielding highly stable PSI supercomplexes with a supramolecular organization identical to the WT.
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Affiliation(s)
- Emilie Wientjes
- Department of Biophysical Chemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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Huber CG, Timperio AM, Toll H, Zolla L. Liquid-chromatography-mass spectrometry of thylakoid membrane proteins. Methods Mol Biol 2009; 492:113-130. [PMID: 19241029 DOI: 10.1007/978-1-59745-493-3_6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The present chapter describes methods for the separation and identification of photosynthetic proteins of thylakoid membranes present in chloroplasts by using different detergents, high-performance liquid chromatography and mass spectrometry. Thylakoid membranes represent a good model for setting up analytical methods suitable for membrane protein characterization.The first step in the procedure is the preparation of purified membrane fractions from plant tissues, followed by the fractionation of membrane proteins by differential solubilization using different detergents. Thus, several protein complexes can be isolated, collected, separated by ion-pair reversed-phase chromatography and detected online by UV-absorption and/or mass spectrometry. Finally, identification of the eluting proteins is accomplished by comparing the molecular mass determined in silico with the molecular mass measured by mass spectrometry.
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Affiliation(s)
- Christian G Huber
- Instrumental Analysis and Bioanalysis, Saarland University, Saarbrücken, Germany
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Grimme RA, Lubner CE, Golbeck JH. Maximizing H2 production in Photosystem I/dithiol molecular wire/platinum nanoparticle bioconjugates. Dalton Trans 2009:10106-13. [DOI: 10.1039/b909137h] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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van Oort B, Amunts A, Borst JW, van Hoek A, Nelson N, van Amerongen H, Croce R. Picosecond fluorescence of intact and dissolved PSI-LHCI crystals. Biophys J 2008; 95:5851-61. [PMID: 18931256 PMCID: PMC2599838 DOI: 10.1529/biophysj.108.140467] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2008] [Accepted: 09/15/2008] [Indexed: 11/18/2022] Open
Abstract
Over the past several years, many crystal structures of photosynthetic pigment-protein complexes have been determined, and these have been used extensively to model spectroscopic results obtained on the same proteins in solution. However, the crystal structure is not necessarily identical to the structure of the protein in solution. Here, we studied picosecond fluorescence of photosystem I light-harvesting complex I (PSI-LHCI), a multisubunit pigment-protein complex that catalyzes the first steps of photosynthesis. The ultrafast fluorescence of PSI-LHCI crystals is identical to that of dissolved crystals, but differs considerably from most kinetics presented in the literature. In contrast to most studies, the data presented here can be modeled quantitatively with only two compartments: PSI core and LHCI. This yields the rate of charge separation from an equilibrated core (22.5 +/- 2.5 ps) and rates of excitation energy transfer from LHCI to core (k(LC)) and vice versa (k(CL)). The ratio between these rates, R = k(CL)/k(LC), appears to be wavelength-dependent and scales with the ratio of the absorption spectra of LHCI and core, indicating the validity of a detailed balance relation between both compartments. k(LC) depends slightly but nonsystematically on detection wavelength, averaging (9.4 +/- 4.9 ps)(-1). R ranges from 0.5 (<690 nm) to approximately 1.3 above 720 nm.
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Affiliation(s)
- Bart van Oort
- Laboratory of Biophysics, Wageningen University, 6703 HA Wageningen, The Netherlands
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Romanowska E, Kargul J, Powikrowska M, Finazzi G, Nield J, Drozak A, Pokorska B. Structural organization of photosynthetic apparatus in agranal chloroplasts of maize. J Biol Chem 2008; 283:26037-46. [PMID: 18632664 PMCID: PMC3258860 DOI: 10.1074/jbc.m803711200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Revised: 07/14/2008] [Indexed: 11/06/2022] Open
Abstract
We investigated the organization of photosystem II (PSII) in agranal bundle sheath thylakoids from a C(4) plant maize. Using blue native/SDS-PAGE and single particle analysis, we show for the first time that PSII in the bundle sheath (BS) chloroplasts exists in a dimeric form and forms light-harvesting complex II (LHCII).PSII supercomplexes. We also demonstrate that a similar set of photosynthetic membrane complexes exists in mesophyll and agranal BS chloroplasts, including intact LHCI.PSI supercomplexes, PSI monomers, PSII core dimers, PSII monomers devoid of CP43, LHCII trimers, LHCII monomers, ATP synthase, and cytochrome b(6)f complex. Fluorescence functional measurements clearly indicate that BS chloroplasts contain PSII complexes that are capable of performing charge separation and are efficiently sensitized by the associated LHCII. We identified a fraction of LHCII present within BS thylakoids that is weakly energetically coupled to the PSII reaction center; however, the majority of BS LHCII is shown to be tightly connected to PSII. Overall, we demonstrate that organization of the photosynthetic apparatus in BS agranal chloroplasts of a model C(4) plant is clearly distinct from that of the stroma lamellae of the C(3) plants. In particular, supramolecular organization of the dimeric LHCII.PSII in the BS thylakoids strongly suggests that PSII in the BS agranal membranes may donate electrons to PSI. We propose that the residual PSII activity may supply electrons to poise cyclic electron flow around PSI and prevent PSI overoxidation, which is essential for the CO(2) fixation in BS cells, and hence, may optimize ATP production within this compartment.
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Affiliation(s)
- Elzbieta Romanowska
- Department of Plant Physiology, University of Warsaw, Miecznikowa 1, 02-096 Warsaw, Poland.
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44
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Kereïche S, Kouřil R, Oostergetel GT, Fusetti F, Boekema EJ, Doust AB, van der Weij-de Wit CD, Dekker JP. Association of chlorophyll a/c2 complexes to photosystem I and photosystem II in the cryptophyte Rhodomonas CS24. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2008; 1777:1122-8. [DOI: 10.1016/j.bbabio.2008.04.045] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Revised: 04/10/2008] [Accepted: 04/22/2008] [Indexed: 11/25/2022]
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45
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Amunts A, Nelson N. Functional organization of a plant Photosystem I: evolution of a highly efficient photochemical machine. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2008; 46:228-37. [PMID: 18272382 DOI: 10.1016/j.plaphy.2007.12.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2007] [Indexed: 05/05/2023]
Abstract
Despite its enormous complexity, a plant Photosystem I (PSI) is arguably the most efficient nano-photochemical machine in Nature. It emerged as a homodimeric structure containing several chlorophyll molecules over 3.5 billion years ago, and has perfected its photoelectric properties ever since. The recently determined structure of plant PSI, which is at the top of the evolutionary tree of this kind of complexes, provided the first relatively high-resolution structural model of the supercomplex containing a reaction center (RC) and a peripheral antenna (LHCI) complexes. The RC is highly homologous to that of the cyanobacterial PSI and maintains the position of most transmembrane helices and chlorophylls during 1.5 years of separate evolution. The LHCI is composed of four nuclear gene products (Lhca1-Lhca4) that are unique among the chlorophyll a/b binding proteins in their pronounced long-wavelength absorbance and their assembly into dimers. In this respect, we describe structural elements, which establish the biological significance of a plant PSI and discuss structural variance from the cyanobacterial version. The present comprehensive structural analysis summarizes our current state of knowledge, providing the first glimpse at the architecture of this highly efficient photochemical machine at the atomic level.
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Affiliation(s)
- Alexey Amunts
- Biochemistry Department, The George S. Wise Faculty of Life Sciences, The Daniella Rich Institute for Structural Biology, Tel Aviv University, Sherman Building, Room 531, Tel Aviv 69978, Israel.
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46
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Zolla L, Rinalducci S, Timperio AM. Proteomic analysis of photosystem I components from different plant species. Proteomics 2007; 7:1866-76. [PMID: 17464937 DOI: 10.1002/pmic.200500053] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In this study, the photosystem I (PSI) highly hydrophobic proteins present within stroma lamellae of the thylakoid membrane were separated by RP-HPLC and identified either by in-solution trypsin digestion peptide fragment fingerprinting or by the close correspondence between the intact mass measurements (IMMs) and those expected from the DNA sequence. Protein identification performed by MS/MS was as reliable as IMMs. Thus, IMM is an easy and valid method for identifying proteins that have no PTMs. This paper reports the M(r) for all PSI proteins in ten different species, including those whose genes have not yet been cloned. Lhca5 was revealed unequivocally in four species, corroborating that it is indeed a protein belonging to the light-harvesting antenna of PSI. In all species examined, the product of the Lhca6 gene has never been revealed. Concerning core proteins, Psa-O has been revealed in three species; isoforms of Psa-D and Psa-E have been found in both monocots and dicots. Small proteins like Psa-I and Psa-J are well separated and identified. RP-HPLC produces reliable fingerprints and reveals that the relative amounts of PSI proteins appear to be markedly different.
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Affiliation(s)
- Lello Zolla
- Department of Environmental Sciences, University of Tuscia, Viterbo, Italy.
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47
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Croce R, Chojnicka A, Morosinotto T, Ihalainen JA, van Mourik F, Dekker JP, Bassi R, van Grondelle R. The low-energy forms of photosystem I light-harvesting complexes: spectroscopic properties and pigment-pigment interaction characteristics. Biophys J 2007; 93:2418-28. [PMID: 17545247 PMCID: PMC1965455 DOI: 10.1529/biophysj.107.106955] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In this work the spectroscopic properties of the special low-energy absorption bands of the outer antenna complexes of higher plant Photosystem I have been investigated by means of low-temperature absorption, fluorescence, and fluorescence line-narrowing experiments. It was found that the red-most absorption bands of Lhca3, Lhca4, and Lhca1-4 peak, respectively, at 704, 708, and 709 nm and are responsible for 725-, 733-, and 732-nm fluorescence emission bands. These bands are more red shifted compared to "normal" chlorophyll a (Chl a) bands present in light-harvesting complexes. The low-energy forms are characterized by a very large bandwidth (400-450 cm(-1)), which is the result of both large homogeneous and inhomogeneous broadening. The observed optical reorganization energy is untypical for Chl a and resembles more that of BChl a antenna systems. The large broadening and the changes in optical reorganization energy are explained by a mixing of an Lhca excitonic state with a charge transfer state. Such a charge transfer state can be stabilized by the polar residues around Chl 1025. It is shown that the optical reorganization energy is changing through the inhomogeneous distribution of the red-most absorption band, with the pigments contributing to the red part of the distribution showing higher values. A second red emission form in Lhca4 was detected at 705 nm and originates from a broad absorption band peaking at 690 nm. This fluorescence emission is present also in the Lhca4-N-47H mutant, which lacks the 733-nm emission band.
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Affiliation(s)
- Roberta Croce
- Department of Biophysical Chemistry, Groningen Bimolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands.
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48
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Gardian Z, Bumba L, Schrofel A, Herbstova M, Nebesarova J, Vacha F. Organisation of Photosystem I and Photosystem II in red alga Cyanidium caldarium: Encounter of cyanobacterial and higher plant concepts. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2007; 1767:725-31. [PMID: 17346666 DOI: 10.1016/j.bbabio.2007.01.021] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2006] [Revised: 01/19/2007] [Accepted: 01/30/2007] [Indexed: 11/25/2022]
Abstract
Structure and organisation of Photosystem I and Photosystem II isolated from red alga Cyanidium caldarium was determined by electron microscopy and single particle image analysis. The overall structure of Photosystem II was found to be similar to that known from cyanobacteria. The location of additional 20 kDa (PsbQ') extrinsic protein that forms part of the oxygen evolving complex was suggested to be in the vicinity of cytochrome c-550 (PsbV) and the 12 kDa (PsbU) protein. Photosystem I was determined as a monomeric unit consisting of PsaA/B core complex with varying amounts of antenna subunits attached. The number of these subunits was seen to be dependent on the light conditions used during cell cultivation. The role of PsaH and PsaG proteins of Photosystem I in trimerisation and antennae complexes binding is discussed.
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Affiliation(s)
- Zdenko Gardian
- Biological Centre, Academy of Sciences of the Czech Republic, Branisovská 31, 370 05 Ceské Budejovice, Czech Republic
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Jensen PE, Bassi R, Boekema EJ, Dekker JP, Jansson S, Leister D, Robinson C, Scheller HV. Structure, function and regulation of plant photosystem I. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2007; 1767:335-52. [PMID: 17442259 DOI: 10.1016/j.bbabio.2007.03.004] [Citation(s) in RCA: 168] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Revised: 03/03/2007] [Accepted: 03/06/2007] [Indexed: 12/20/2022]
Abstract
Photosystem I (PSI) is a multisubunit protein complex located in the thylakoid membranes of green plants and algae, where it initiates one of the first steps of solar energy conversion by light-driven electron transport. In this review, we discuss recent progress on several topics related to the functioning of the PSI complex, like the protein composition of the complex in the plant Arabidopsis thaliana, the function of these subunits and the mechanism by which nuclear-encoded subunits can be inserted into or transported through the thylakoid membrane. Furthermore, the structure of the native PSI complex in several oxygenic photosynthetic organisms and the role of the chlorophylls and carotenoids in the antenna complexes in light harvesting and photoprotection are reviewed. The special role of the 'red' chlorophylls (chlorophyll molecules that absorb at longer wavelength than the primary electron donor P700) is assessed. The physiology and mechanism of the association of the major light-harvesting complex of photosystem II (LHCII) with PSI during short term adaptation to changes in light quality and quantity is discussed in functional and structural terms. The mechanism of excitation energy transfer between the chlorophylls and the mechanism of primary charge separation is outlined and discussed. Finally, a number of regulatory processes like acclimatory responses and retrograde signalling is reviewed with respect to function of the thylakoid membrane. We finish this review by shortly discussing the perspectives for future research on PSI.
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Affiliation(s)
- Poul Erik Jensen
- Plant Biochemistry Laboratory, Department of Plant Biology, Faculty of Life Science, University of Copenhagen, DK-1871 Frederiksberg C, Denmark.
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50
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Qin X, Wang K, Chen X, Qu Y, Li L, Kuang T. Rapid purification of photosystem I chlorophyll-binding proteins by differential centrifugation and vertical rotor. PHOTOSYNTHESIS RESEARCH 2006; 90:195-204. [PMID: 17235493 DOI: 10.1007/s11120-006-9104-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2006] [Accepted: 08/30/2006] [Indexed: 05/13/2023]
Abstract
Photosystem I (PSI), which consists of a core complex and light-harvesting complex I (LHCI), is an important multisubunit pigment-protein complex located in the photosynthetic membranes of cyanobacteria, algae and plants. In the present study, we described a rapid method for isolation and purification of PSI and its subfractions. For purification of PSI, crude PSI was first prepared by differential centrifugation, which was applicable on a large scale at low cost. Then PSI was purified by sucrose gradient ultracentrifugation in a vertical rotor to reduce the centrifugation time from more than 20 h when using a swinging bucket rotor to only 3 h. Similarly, for subfractionation of PSI into the core complex and light-harvesting complex I, sucrose gradient ultracentrifugation in a vertical rotor was also used and it took only 4 h to obtain the PSI core, LHCI-680, and LHCI-730 at the same time. The resulting preparations were characterized by sodium dodecyl-sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), absorption spectroscopy, and 77 K fluorescence spectroscopy. In addition, their pigment composition was analyzed by high-performance liquid chromatography and the results showed that each Lhca could bind 1.5-1.6 luteins, 1.0 Violaxanthins, and 0.8-1.1 beta-carotenes on average, demonstrating that fewer carotenoids were released than with the slower traditional centrifugation. These results showed that the rapid isolation procedure, based on differential centrifugation and sucrose gradient ultracentrifugation in a vertical rotor, was efficient, and it should significantly facilitate preparation and studies of plant PSI. Moreover, the vertical rotor, rather than the swinging bucket rotor, may be a good choice for isolation of some other proteins.
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Affiliation(s)
- Xiaochun Qin
- Key Laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese Academy of Sciences, Beijing , 100093, P.R. China
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