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van Stokkum IHM, Müller MG, Holzwarth AR. Energy Transfer and Radical-Pair Dynamics in Photosystem I with Different Red Chlorophyll a Pigments. Int J Mol Sci 2024; 25:4125. [PMID: 38612934 PMCID: PMC11012434 DOI: 10.3390/ijms25074125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/03/2024] [Accepted: 04/06/2024] [Indexed: 04/14/2024] Open
Abstract
We establish a general kinetic scheme for the energy transfer and radical-pair dynamics in photosystem I (PSI) of Chlamydomonas reinhardtii, Synechocystis PCC6803, Thermosynechococcus elongatus and Spirulina platensis grown under white-light conditions. With the help of simultaneous target analysis of transient-absorption data sets measured with two selective excitations, we resolved the spectral and kinetic properties of the different species present in PSI. WL-PSI can be described as a Bulk Chl a in equilibrium with a higher-energy Chl a, one or two Red Chl a and a reaction-center compartment (WL-RC). Three radical pairs (RPs) have been resolved with very similar properties in the four model organisms. The charge separation is virtually irreversible with a rate of ≈900 ns-1. The second rate, of RP1 → RP2, ranges from 70-90 ns-1 and the third rate, of RP2 → RP3, is ≈30 ns-1. Since RP1 and the Red Chl a are simultaneously present, resolving the RP1 properties is challenging. In Chlamydomonas reinhardtii, the excited WL-RC and Bulk Chl a compartments equilibrate with a lifetime of ≈0.28 ps, whereas the Red and the Bulk Chl a compartments equilibrate with a lifetime of ≈2.65 ps. We present a description of the thermodynamic properties of the model organisms at room temperature.
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Affiliation(s)
- Ivo H. M. van Stokkum
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands;
| | - Marc G. Müller
- Max-Planck-Institut für Chemische Energiekonversion, D-45470 Mülheim a.d. Ruhr, Germany;
| | - Alfred R. Holzwarth
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands;
- Max-Planck-Institut für Chemische Energiekonversion, D-45470 Mülheim a.d. Ruhr, Germany;
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2
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Fujita Y, Zhang X, Mohamed A, Ye S, Shibata Y. Accumulation of quenched LHCII around PSI in Chlamydomonas cells in state2 revealed by cryo-fluorescence lifetime imaging. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2022; 236:112584. [PMID: 36272337 DOI: 10.1016/j.jphotobiol.2022.112584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 09/20/2022] [Accepted: 10/02/2022] [Indexed: 02/17/2023]
Abstract
Fluorescence-spectral microscope observations of photosynthetic organisms at cryogenic temperatures have the ability to spectrally resolve the two photosystems (PSs) and thus provide a powerful tool to elucidate the functional analysis of photosynthesis in vivo. In the present study, a measurement channel of the fluorescence lifetime at 680 nm was added to the cryo-microscope system previously developed by the authors. This provides access to information on the functional state of the light-harvesting system in living cells during regulation by a mechanism called state transitions. The observations of state1-locked and state2-locked Chlamydomonas cells at 80 K enabled us to identify a component showing rapidly decaying fluorescence with a lifetime of ca. 3 ps and emitting at around 676 nm. The component was assigned to the light-harvesting complex II (LHCII) that is isolated from both PSs and in a quenched state, probably due to the formation of aggregates. Simultaneous spectral observations revealed the accumulation of this free LHCII in the photosystem I (PSI)-enriched region within each state2-locked cell. To the best of our knowledge, this is the first in-vivo observation which suggests the localization of the quenched LHCII aggregates.
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Affiliation(s)
- Yuki Fujita
- Department of Chemistry, Graduate School of Sciences, Tohoku University, 980-8578 Sendai, Japan
| | - XianJun Zhang
- Department of Chemistry, Graduate School of Sciences, Tohoku University, 980-8578 Sendai, Japan; Division for Interdisciplinary Advanced Research and Education, Tohoku University, 980-8578 Sendai, Japan
| | - Ahmed Mohamed
- Department of Chemistry, Graduate School of Sciences, Tohoku University, 980-8578 Sendai, Japan
| | - Shen Ye
- Department of Chemistry, Graduate School of Sciences, Tohoku University, 980-8578 Sendai, Japan
| | - Yutaka Shibata
- Department of Chemistry, Graduate School of Sciences, Tohoku University, 980-8578 Sendai, Japan.
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Fang Y, Liu D, Jiang J, He A, Zhu R, Tian L. Photoprotective energy quenching in the red alga Porphyridium purpureum occurs at the core antenna of the photosystem II but not at its reaction center. J Biol Chem 2022; 298:101783. [PMID: 35245502 PMCID: PMC8978274 DOI: 10.1016/j.jbc.2022.101783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 02/24/2022] [Accepted: 02/26/2022] [Indexed: 01/01/2023] Open
Abstract
Photosynthetic organisms have evolved light-harvesting antennae over time. In cyanobacteria, external phycobilisomes (PBSs) are the dominant antennae, whereas in green algae and higher plants, PBSs have been replaced by proteins of the Lhc family that are integrated in the membrane. Red algae represent an evolutionary intermediate between these two systems, as they employ both PBSs and membrane LHCR proteins as light-harvesting units. Understanding how red algae cope with light is not only interesting for biotechnological applications, but is also of evolutionary interest. For example, energy-dependent quenching (qE) is an essential photoprotective mechanism widely used by species from cyanobacteria to higher plants to avoid light damage; however, the quenching mechanism in red algae remains largely unexplored. Here, we used both pulse amplitude-modulated (PAM) and time-resolved chlorophyll fluorescence to characterize qE kinetics in the red alga Porphyridium purpureum. PAM traces confirmed that qE in P. purpureum is activated by a decrease in the thylakoid lumen pH, whereas time-resolved fluorescence results further revealed the quenching site and ultrafast quenching kinetics. We found that quenching exclusively takes place in the photosystem II (PSII) complexes and preferentially occurs at PSII’s core antenna rather than at its reaction center, with an overall quenching rate of 17.6 ± 3.0 ns−1. In conclusion, we propose that qE in red algae is not a reaction center type of quenching, and that there might be a membrane-bound protein that resembles PsbS of higher plants or LHCSR of green algae that senses low luminal pH and triggers qE in red algae.
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Affiliation(s)
- Yuan Fang
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Dongyang Liu
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Jingjing Jiang
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Axin He
- State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, School of Physics, Peking University, Beijing, China
| | - Rui Zhu
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, China
| | - Lijin Tian
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing, China.
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Cecchin M, Jeong J, Son W, Kim M, Park S, Zuliani L, Cazzaniga S, Pompa A, Young Kang C, Bae S, Ballottari M, Jin E. LPA2 protein is involved in photosystem II assembly in Chlamydomonas reinhardtii. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 107:1648-1662. [PMID: 34218480 PMCID: PMC8518032 DOI: 10.1111/tpj.15405] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 06/23/2021] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Photosynthetic eukaryotes require the proper assembly of photosystem II (PSII) in order to strip electrons from water and fuel carbon fixation reactions. In Arabidopsis thaliana, one of the PSII subunits (CP43/PsbC) was suggested to be assembled into the PSII complex via its interaction with an auxiliary protein called Low PSII Accumulation 2 (LPA2). However, the original articles describing the role of LPA2 in PSII assembly have been retracted. To investigate the function of LPA2 in the model organism for green algae, Chlamydomonas reinhardtii, we generated knockout lpa2 mutants by using the CRISPR-Cas9 target-specific genome editing system. Biochemical analyses revealed the thylakoidal localization of LPA2 protein in the wild type (WT), whereas lpa2 mutants were characterized by a drastic reduction in the levels of D1, D2, CP47 and CP43 proteins. Consequently, reduced PSII supercomplex accumulation, chlorophyll content per cell, PSII quantum yield and photosynthetic oxygen evolution were measured in the lpa2 mutants, leading to the almost complete impairment of photoautotrophic growth. Pulse-chase experiments demonstrated that the absence of LPA2 protein caused reduced PSII assembly and reduced PSII turnover. Taken together, our data indicate that, in C. reinhardtii, LPA2 is required for PSII assembly and proper function.
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Affiliation(s)
- Michela Cecchin
- Dipartimento di BiotecnologieUniversità di VeronaStrada le Grazie 15Verona37134Italy
| | - Jooyeon Jeong
- Department of Life ScienceHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Woojae Son
- Department of ChemistryHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Minjae Kim
- Department of Life ScienceHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Seunghye Park
- Department of Life ScienceHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Luca Zuliani
- Dipartimento di BiotecnologieUniversità di VeronaStrada le Grazie 15Verona37134Italy
| | - Stefano Cazzaniga
- Dipartimento di BiotecnologieUniversità di VeronaStrada le Grazie 15Verona37134Italy
| | - Andrea Pompa
- Dipartimento di Scienze BiomolecolariUniversità degli studi di UrbinoVia Aurelio Saffi, 2Urbino61029Italy
- Istituto di Bioscienze e BiorisorseConsiglio Nazionale delle RicercheVia Madonna Alta, 130Perugia06128Italy
| | - Chan Young Kang
- Department of ChemistryHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Sangsu Bae
- Department of ChemistryHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
| | - Matteo Ballottari
- Dipartimento di BiotecnologieUniversità di VeronaStrada le Grazie 15Verona37134Italy
| | - EonSeon Jin
- Department of Life ScienceHanyang University222, Wangsimni‐ro, Seongdong‐guSeoul04763Korea
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Upadhyaya S, Rao BJ. Reciprocal regulation of photosynthesis and mitochondrial respiration by TOR kinase in Chlamydomonas reinhardtii. PLANT DIRECT 2019; 3:e00184. [PMID: 31832599 PMCID: PMC6854518 DOI: 10.1002/pld3.184] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 10/21/2019] [Accepted: 10/29/2019] [Indexed: 05/03/2023]
Abstract
While the role of TOR kinase in the chloroplast biogenesis and transcriptional regulation of photosynthesis is well documented in Arabidopsis, the functional relevance of this metabolic sensor kinase in chloroplast-mitochondria cross talk is unknown. Using Chlamydomonas reinhardtii as the model system, we demonstrate the role of TOR kinase in the regulation of chloroplast and mitochondrial functions: We show that TOR kinase inhibition impairs the maintenance of high ETR associated with PSII and low NPQ and inhibits efficient state transitions between PSII and PSI. While compromised photosynthetic functions are observed in TOR kinase inhibited cells, same conditions lead to augmentation in mitochondrial basal respiration rate by twofold and concomitantly a rise in ATP production. Interestingly, such upregulated mitochondrial functions in TOR-inhibited cells are mediated by fragmented mitochondria via upregulating COXIIb and downregulating Hxk1 and AOX1 protein levels. We propose that TOR kinase may act as a sensor that counter-regulates chloroplast versus mitochondrial functions in a normal C. reinhardtii cell.
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Affiliation(s)
- Shivani Upadhyaya
- Department of Biological SciencesTata Institute of Fundamental Research (TIFR)MumbaiIndia
| | - Basuthkar Jagadeeshwar Rao
- Indian Institute of Science Education and Research (IISER) TirupatiTransit Campus: Sree Rama Engineering CollegeTirupatiIndia
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6
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Macroorganisation and flexibility of thylakoid membranes. Biochem J 2019; 476:2981-3018. [DOI: 10.1042/bcj20190080] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Revised: 09/19/2019] [Accepted: 10/03/2019] [Indexed: 02/07/2023]
Abstract
Abstract
The light reactions of photosynthesis are hosted and regulated by the chloroplast thylakoid membrane (TM) — the central structural component of the photosynthetic apparatus of plants and algae. The two-dimensional and three-dimensional arrangement of the lipid–protein assemblies, aka macroorganisation, and its dynamic responses to the fluctuating physiological environment, aka flexibility, are the subject of this review. An emphasis is given on the information obtainable by spectroscopic approaches, especially circular dichroism (CD). We briefly summarise the current knowledge of the composition and three-dimensional architecture of the granal TMs in plants and the supramolecular organisation of Photosystem II and light-harvesting complex II therein. We next acquaint the non-specialist reader with the fundamentals of CD spectroscopy, recent advances such as anisotropic CD, and applications for studying the structure and macroorganisation of photosynthetic complexes and membranes. Special attention is given to the structural and functional flexibility of light-harvesting complex II in vitro as revealed by CD and fluorescence spectroscopy. We give an account of the dynamic changes in membrane macroorganisation associated with the light-adaptation of the photosynthetic apparatus and the regulation of the excitation energy flow by state transitions and non-photochemical quenching.
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Wlodarczyk LM, Snellenburg JJ, Dekker JP, Stokkum IHM. Development of fluorescence quenching in Chlamydomonas reinhardtii upon prolonged illumination at 77 K. PHOTOSYNTHESIS RESEARCH 2018; 137:503-513. [PMID: 29948747 PMCID: PMC6182390 DOI: 10.1007/s11120-018-0534-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 06/11/2018] [Indexed: 06/08/2023]
Abstract
Low-temperature fluorescence measurements are frequently used in photosynthesis research to assess photosynthetic processes. Upon illumination of photosystem II (PSII) frozen to 77 K, fluorescence quenching is observed. In this work, we studied the light-induced quenching in intact cells of Chlamydomonas reinhardtii at 77 K using time-resolved fluorescence spectroscopy with a streak camera setup. In agreement with previous studies, global analysis of the data shows that prolonged illumination of the sample affects the nanosecond decay component of the PSII emission. Using target analysis, we resolved the quenching on the PSII-684 compartment which describes bulk chlorophyll molecules of the PSII core antenna. Further, we quantified the quenching rate constant and observed that as the illumination proceeds the accumulation of the quencher leads to a speed up of the fluorescence decay of the PSII-684 compartment as the decay rate constant increases from about 3 to 4 ns- 1. The quenching on PSII-684 leads to indirect quenching of the compartments PSII-690 and PSII-695 which represent the red chlorophyll of the PSII core. These results explain past and current observations of light-induced quenching in 77 K steady-state and time-resolved fluorescence spectra.
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Affiliation(s)
- Lucyna M Wlodarczyk
- LaserLaB, Department of Physics and Astronomy, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands
| | - Joris J Snellenburg
- LaserLaB, Department of Physics and Astronomy, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands
| | - Jan P Dekker
- LaserLaB, Department of Physics and Astronomy, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands
| | - Ivo H M Stokkum
- LaserLaB, Department of Physics and Astronomy, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands.
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8
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Fujita Y, Ito W, Washiyama K, Shibata Y. Imaging of intracellular rearrangement of photosynthetic proteins in Chlamydomonas cells upon state transition. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2018; 185:111-116. [DOI: 10.1016/j.jphotobiol.2018.05.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 05/22/2018] [Accepted: 05/27/2018] [Indexed: 01/09/2023]
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9
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Acuña AM, Lemaire C, van Grondelle R, Robert B, van Stokkum IHM. Energy transfer and trapping in Synechococcus WH 7803. PHOTOSYNTHESIS RESEARCH 2018; 135:115-124. [PMID: 29030777 PMCID: PMC5784009 DOI: 10.1007/s11120-017-0451-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 09/26/2017] [Indexed: 05/28/2023]
Abstract
Excitation energy transfer (EET) and trapping in Synechococcus WH 7803 whole cells and isolated photosystem I (PSI) complexes have been studied by time-resolved emission spectroscopy at room temperature (RT) and at 77 K. With the help of global and target analysis, the pathways of EET and the charge separation dynamics have been identified. Energy absorbed in the phycobilisome (PB) rods by the abundant phycoerythrin (PE) is funneled to phycocyanin (PC645) and from there to the core that contains allophycocyanin (APC660 and APC680). Intra-PB EET rates have been estimated to range from 11 to 68/ns. It was estimated that at RT, the terminal emitter of the phycobilisome, APC680, transfers its energy at a rate of 90/ns to PSI and at a rate of 50/ns to PSII. At 77 K, the redshifted Chl a states in the PSI core were heterogeneous, with maximum emission at 697 and 707 nm. In 72% of the PSI complexes, the bulk Chl a in equilibrium with F697 decayed with a main trapping lifetime of 39 ps.
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Affiliation(s)
- Alonso M Acuña
- Faculty of Science, Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Vrije Universiteit, Amsterdam, Netherlands
| | - Claire Lemaire
- CEA, Institut de Biologie et de Technologies de Saclay, and CNRS, 91191, Gif/Yvette Cedex, France
| | - Rienk van Grondelle
- Faculty of Science, Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Vrije Universiteit, Amsterdam, Netherlands
| | - Bruno Robert
- Faculty of Science, Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Vrije Universiteit, Amsterdam, Netherlands
- CEA, Institut de Biologie et de Technologies de Saclay, and CNRS, 91191, Gif/Yvette Cedex, France
| | - Ivo H M van Stokkum
- Faculty of Science, Department of Physics and Astronomy and Institute for Lasers, Life and Biophotonics, Vrije Universiteit, Amsterdam, Netherlands.
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Lucker B, Schwarz E, Kuhlgert S, Ostendorf E, Kramer DM. Spectroanalysis in native gels (SING): rapid spectral analysis of pigmented thylakoid membrane complexes separated by CN-PAGE. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2017; 92:744-756. [PMID: 28865165 DOI: 10.1111/tpj.13703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 08/22/2017] [Accepted: 08/29/2017] [Indexed: 06/07/2023]
Abstract
Photosynthetic organisms rapidly adjust the capture, transfer and utilization of light energy to optimize the efficiency of photosynthesis and avoid photodamage. These adjustments involve fine-tuning of expression levels and mutual interactions among electron/proton transfer components and their associated light-harvesting antenna. Detailed studies of these interactions and their dynamics have been hindered by the low throughput and resolution of currently available research tools, which involve laborious isolation, separation and characterization steps. To address these issues, we developed an approach that measured multiple spectroscopic properties of thylakoid preparations directly in native polyacrylamide gel electrophoresis gels, enabling unprecedented resolution of photosynthetic complexes, both in terms of the spectroscopic and functional details, as well as the ability to distinguish separate complexes and thus test their functional connections. As a demonstration, we explore the thylakoid membrane components of Chlamydomonas reinhardtii acclimated to high and low light, using a combination of room temperature absorption and 77K fluorescence emission to generate a multi-dimensional molecular and spectroscopic map of the photosynthetic apparatus. We show that low-light-acclimated cells accumulate a photosystem I-containing megacomplex that is absent in high-light-acclimated cells and contains distinct LhcII proteins that can be distinguished based on their spectral signatures.
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Affiliation(s)
- Ben Lucker
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - Eliezer Schwarz
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - Sebastian Kuhlgert
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - Elisabeth Ostendorf
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
| | - David M Kramer
- Department of Biochemistry and Molecular Biology, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
- DOE-Plant Research Laboratory, S222 Plant Biology Building, Michigan State University, East Lansing, MI, 48824-1312, USA
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