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Chrupková P, van Stokkum IHM, Friedrich T, Moldenhauer M, Budisa N, Tseng HW, Polívka T, Cherepanov DA, Maksimov EG, Kloz M. Raman Vibrational Signatures of Excited States of Echinenone in the Orange Carotenoid Protein (OCP) and Implications for its Photoactivation Mechanism. J Mol Biol 2024; 436:168625. [PMID: 38797429 DOI: 10.1016/j.jmb.2024.168625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 05/09/2024] [Accepted: 05/17/2024] [Indexed: 05/29/2024]
Abstract
In this study, the vibrational characteristics of optically excited echinenone in various solvents and the Orange Carotenoid Protein (OCP) in red and orange states are systematically investigated through steady-state and time-resolved spectroscopy techniques. Time-resolved experiments, employing both Transient Absorption (TA) and Femtosecond Stimulated Raman Spectroscopy (FSRS), reveal different states in the OCP photoactivation process. The time-resolved studies indicate vibrational signatures of exited states positioned above the S1 state during the initial 140 fs of carotenoid evolution in OCP, an absence of a vibrational signature for the relaxed S1 state of echinenone in OCP, and more robust signatures of a highly excited ground state (GS) in OCP. Differences in S1 state vibration population signatures between OCP and solvents are attributed to distinct conformations of echinenone in OCP and hydrogen bonds at the keto group forming a short-lived intramolecular charge transfer (ICT) state. The vibrational dynamics of the hot GS in OCP show a more pronounced red shift of ground state CC vibration compared to echinenone in solvents, thus suggesting an unusually hot form of GS. The study proposes a hypothesis for the photoactivation mechanism of OCP, emphasizing the high level of vibrational excitation in longitudinal stretching modes as a driving force. In conclusion, the comparison of vibrational signatures reveals unique dynamics of energy dissipation in OCP, providing insights into the photoactivation mechanism and highlighting the impact of the protein environment on carotenoid behavior. The study underscores the importance of vibrational analysis in understanding the intricate processes involved in early phase OCP photoactivation.
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Affiliation(s)
- Petra Chrupková
- The Extreme Light Infrastructure ERIC, ELI Beamlines Facility, Za Radnicí 835, Dolní Břežany, Czech Republic; University of South Bohemia in České Budějovice, Faculty of Science, Branišovská 1760, 370 05 České Budějovice, Czech Republic
| | - Ivo H M van Stokkum
- Vrije Universiteit, Department of Physics and Astronomy, Faculty of Sciences, De Boelelaan 1081, 1081HV Amsterdam, the Netherlands
| | - Thomas Friedrich
- Technische Universität Berlin, Institute of Chemistry PC 14, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Marcus Moldenhauer
- Technische Universität Berlin, Institute of Chemistry PC 14, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Nediljko Budisa
- University of Manitoba, Department of Chemistry, 144 Dysart Rd, 360 Parker Building, Winnipeg, MB R3T 2N2, Canada
| | - Hsueh-Wei Tseng
- University of Manitoba, Department of Chemistry, 144 Dysart Rd, 360 Parker Building, Winnipeg, MB R3T 2N2, Canada
| | - Tomáš Polívka
- University of South Bohemia in České Budějovice, Faculty of Science, Branišovská 1760, 370 05 České Budějovice, Czech Republic
| | - Dmitry A Cherepanov
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 142432 Moscow, Russian Federation; Lomonosov Moscow State University, A.N. Belozersky Institute of Physical-Chemical Biology, 119991 Moscow, Russian Federation
| | - Eugene G Maksimov
- Lomonosov Moscow State University, Faculty of Biology, Vorobyovy Gory 1-12, Moscow 119991, Russian Federation
| | - Miroslav Kloz
- The Extreme Light Infrastructure ERIC, ELI Beamlines Facility, Za Radnicí 835, Dolní Břežany, Czech Republic.
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2
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Kerfeld CA, Sutter M. Orange carotenoid proteins: structural understanding of evolution and function. Trends Biochem Sci 2024:S0968-0004(24)00110-5. [PMID: 38789305 DOI: 10.1016/j.tibs.2024.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/15/2024] [Accepted: 04/30/2024] [Indexed: 05/26/2024]
Abstract
Cyanobacteria uniquely contain a primitive water-soluble carotenoprotein, the orange carotenoid protein (OCP). Nearly all extant cyanobacterial genomes contain genes for the OCP or its homologs, implying an evolutionary constraint for cyanobacteria to conserve its function. Genes encoding the OCP and its two constituent structural domains, the N-terminal domain, helical carotenoid proteins (HCPs), and its C-terminal domain, are found in the most basal lineages of extant cyanobacteria. These three carotenoproteins exemplify the importance of the protein for carotenoid properties, including protein dynamics, in response to environmental changes in facilitating a photoresponse and energy quenching. Here, we review new structural insights for these carotenoproteins and situate the role of the protein in what is currently understood about their functions.
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Affiliation(s)
- Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
| | - Markus Sutter
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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3
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Leccese S, Calcinoni A, Wilson A, Kirilovsky D, Carbonera D, Onfroy T, Jolivalt C, Mezzetti A. Orange Carotenoid Protein in Mesoporous Silica: A New System towards the Development of Colorimetric and Fluorescent Sensors for pH and Temperature. MICROMACHINES 2023; 14:1871. [PMID: 37893308 PMCID: PMC10609006 DOI: 10.3390/mi14101871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 09/26/2023] [Accepted: 09/26/2023] [Indexed: 10/29/2023]
Abstract
Orange carotenoid protein (OCP) is a photochromic carotenoprotein involved in the photoprotection of cyanobacteria. It is activated by blue-green light to a red form OCPR capable of dissipating the excess of energy of the cyanobacterial photosynthetic light-harvesting systems. Activation to OCPR can also be achieved in the dark. In the present work, activation by pH changes of two different OCPs-containing echinenone or canthaxanthin as carotenoids-is investigated in different conditions. A particular emphasis is put on OCP encapsulated in SBA-15 mesoporous silica nanoparticles. It is known that in these hybrid systems, under appropriate conditions, OCP remains photoactive. Here, we show that when immobilised in SBA-15, the OCP visible spectrum is sensitive to pH changes, but such a colorimetric response is very different from the one observed for OCP in solution. In both cases (SBA-15 matrices and solutions), pH-induced colour changes are related either by orange-to-red OCP activation, or by carotenoid loss from the denatured protein. Of particular interest is the response of OCP in SBA-15 matrices, where a sudden change in the Vis absorption spectrum and in colour is observed for pH changing from 2 to 3 (in the case of canthaxanthin-binding OCP in SBA-15: λMAX shifts from 454 to 508 nm) and for pH changing from 3 to 4 (in the case of echinenone-binding OCP in SBA-15: λMAX shifts from 445 to 505 nm). The effect of temperature on OCP absorption spectrum and colour (in SBA-15 matrices) has also been investigated and found to be highly dependent on the properties of the used mesoporous silica matrix. Finally, we also show that simultaneous encapsulation in selected surface-functionalised SBA-15 nanoparticles of appropriate fluorophores makes it possible to develop OCP-based pH-sensitive fluorescent systems. This work therefore represents a proof of principle that OCP immobilised in mesoporous silica is a promising system in the development of colorimetric and fluorometric pH and temperature sensors.
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Affiliation(s)
- Silvia Leccese
- Sorbonne Université, CNRS, Laboratoire de Réactivité de Surface (LRS), 4 Place Jussieu, 75005 Paris, France (A.C.); (C.J.)
| | - Andrea Calcinoni
- Sorbonne Université, CNRS, Laboratoire de Réactivité de Surface (LRS), 4 Place Jussieu, 75005 Paris, France (A.C.); (C.J.)
- Department of Chemical Sciences, University of Padova, 35131 Padova, Italy;
| | - Adjélé Wilson
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, CEDEX, 91198 Gif-sur-Yvette, France (D.K.)
| | - Diana Kirilovsky
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, CEDEX, 91198 Gif-sur-Yvette, France (D.K.)
| | | | - Thomas Onfroy
- Sorbonne Université, CNRS, Laboratoire de Réactivité de Surface (LRS), 4 Place Jussieu, 75005 Paris, France (A.C.); (C.J.)
| | - Claude Jolivalt
- Sorbonne Université, CNRS, Laboratoire de Réactivité de Surface (LRS), 4 Place Jussieu, 75005 Paris, France (A.C.); (C.J.)
| | - Alberto Mezzetti
- Sorbonne Université, CNRS, Laboratoire de Réactivité de Surface (LRS), 4 Place Jussieu, 75005 Paris, France (A.C.); (C.J.)
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Han MH, Yang HW, Yoon J, Villafani Y, Song JY, Pan CH, Park K, Cho Y, Song JJ, Kim SJ, Park YI, Park J. Color-Tuning Mechanism of the Lit Form of Orange Carotenoid Protein. Mol Cells 2023; 46:513-525. [PMID: 37587751 PMCID: PMC10440265 DOI: 10.14348/molcells.2023.2186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 07/11/2023] [Accepted: 07/13/2023] [Indexed: 08/18/2023] Open
Abstract
Orange carotenoid protein (OCP) of photosynthetic cyanobacteria binds to ketocarotenoids noncovalently and absorbs excess light to protect the host organism from light-induced oxidative damage. Herein, we found that mutating valine 40 in the α3 helix of Gloeocapsa sp. PCC 7513 (GlOCP1) resulted in blue- or red-shifts of 6-20 nm in the absorption maxima of the lit forms. We analyzed the origins of absorption maxima shifts by integrating X-ray crystallography, homology modeling, molecular dynamics simulations, and hybrid quantum mechanics/molecular mechanics calculations. Our analysis suggested that the single residue mutations alter the polar environment surrounding the bound canthaxanthin, thereby modulating the degree of charge transfer in the photoexcited state of the chromophore. Our integrated investigations reveal the mechanism of color adaptation specific to OCPs and suggest a design principle for color-specific photoswitches.
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Affiliation(s)
- Man-Hyuk Han
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
- Department of Biological Sciences, KI for the BioCentury, KAIST, Daejeon 34141, Korea
| | - Hee Wook Yang
- Department of Biological Sciences, Chungnam National University, Daejeon 34134, Korea
| | - Jungmin Yoon
- Department of Biological Sciences, KI for the BioCentury, KAIST, Daejeon 34141, Korea
| | - Yvette Villafani
- Department of Biological Sciences, Chungnam National University, Daejeon 34134, Korea
| | - Ji-Young Song
- Department of Biological Sciences, Chungnam National University, Daejeon 34134, Korea
| | - Cheol Ho Pan
- Natural Product Informatics Research Center, KIST Gangneung Institute of Natural Products, Gangneung 25451, Korea
| | - Keunwan Park
- Natural Product Informatics Research Center, KIST Gangneung Institute of Natural Products, Gangneung 25451, Korea
| | - Youngmoon Cho
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
| | - Ji-Joon Song
- Department of Biological Sciences, KI for the BioCentury, KAIST, Daejeon 34141, Korea
| | - Seung Joong Kim
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea
- Quantum Intelligence Corp., Seoul 07326, Korea
| | - Youn-Il Park
- Department of Biological Sciences, Chungnam National University, Daejeon 34134, Korea
| | - Jiyong Park
- Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science (IBS), Daejeon 34141, Korea
- Department of Chemistry, KAIST, Daejeon 34141, Korea
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5
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Leccese S, Wilson A, Kirilovsky D, Spezia R, Jolivalt C, Mezzetti A. Light-induced infrared difference spectroscopy on three different forms of orange carotenoid protein: focus on carotenoid vibrations. Photochem Photobiol Sci 2023:10.1007/s43630-023-00384-7. [PMID: 36853495 DOI: 10.1007/s43630-023-00384-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 01/27/2023] [Indexed: 03/01/2023]
Abstract
Orange carotenoid protein (OCP) is a photoactive carotenoprotein involved in photoprotection of cyanobacteria, which uses a keto-catorenoid as a chromophore. When it absorbs blue-green light, it converts from an inactive OCPO orange form to an activated OCPR red form, the latter being able to bind the light-harvesting complexes facilitating thermal dissipation of the excess of absorbed light energy. Several research groups have focused their attention on the photoactivation mechanism, characterized by several steps, involving both carotenoid photophysics and protein conformational changes. Among the used techniques, time-resolved IR spectroscopy have the advantage of providing simultaneously information on both the chromophore and the protein, giving thereby the possibility to explore links between carotenoid dynamics and protein dynamics, leading to a better understanding of the mechanism. However, an appropriate interpretation of data requires previous assignment of marker IR bands, for both the carotenoid and the protein. To date, some assignments have concerned specific α-helices of the OCP backbone, but no specific marker band for the carotenoid was identified on solid ground. This paper provides evidence for the assignment of putative marker bands for three carotenoids bound in three different OCPs: 3'-hydroxyechineone (3'-hECN), echinenone (ECN), canthaxanthin (CAN). Light-induced FTIR difference spectra were recorded in H2O and D2O and compared with spectra of isolated carotenoids. The use of DFT calculations allowed to propose a description for the vibrations responsible of several IR bands. Interestingly, most bands are located at the same wavenumber for the three kinds of OCPs suggesting that the conformation of the three carotenoids is the same in the red and in the orange form. These results are discussed in the framework of recent time-resolved IR studies on OCP.
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Affiliation(s)
- Silvia Leccese
- Laboratoire de Réactivité de Surface, LRS, Sorbonne Université, CNRS, 4 Place Jussieu, 75005, Paris, France
| | - Adjélé Wilson
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, 91198, Gif Sur Yvette, France
| | - Diana Kirilovsky
- Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, CEA, CNRS, 91198, Gif Sur Yvette, France
| | - Riccardo Spezia
- Laboratoire de Chimie Théorique, Sorbonne Université, UMR 7616 CNRS, 4, Place Jussieu, 75005, Paris, France
| | - Claude Jolivalt
- Laboratoire de Réactivité de Surface, LRS, Sorbonne Université, CNRS, 4 Place Jussieu, 75005, Paris, France
| | - Alberto Mezzetti
- Laboratoire de Réactivité de Surface, LRS, Sorbonne Université, CNRS, 4 Place Jussieu, 75005, Paris, France.
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6
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Piccinini L, Iacopino S, Cazzaniga S, Ballottari M, Giuntoli B, Licausi F. A synthetic switch based on orange carotenoid protein to control blue-green light responses in chloroplasts. PLANT PHYSIOLOGY 2022. [PMID: 35289909 DOI: 10.1101/2021.01.27.428448] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Synthetic biology approaches to engineer light-responsive systems are widely used, but their applications in plants are still limited due to the interference with endogenous photoreceptors and the intrinsic requirement of light for photosynthesis. Cyanobacteria possess a family of soluble carotenoid-associated proteins named orange carotenoid proteins (OCPs) that, when activated by blue-green light, undergo a reversible conformational change that enables the photoprotection mechanism that occurs on the phycobilisome. Exploiting this system, we developed a chloroplast-localized synthetic photoswitch based on a protein complementation assay where two nanoluciferase fragments were fused to separate polypeptides corresponding to the OCP2 domains. Since Arabidopsis (Arabidopsis thaliana) does not possess the prosthetic group needed for the assembly of the OCP2 complex, we first implemented the carotenoid biosynthetic pathway with a bacterial β-carotene ketolase enzyme (crtW) to generate keto-carotenoid-producing plants. The photoswitch was tested and characterized in Arabidopsis protoplasts and stably transformed plants with experiments aimed to uncover its regulation by a range of light intensities, wavelengths, and its conversion dynamics. Finally, we applied the OCP-based photoswitch to control transcriptional responses in chloroplasts in response to green light illumination by fusing the two OCP fragments with the plastidial SIGMA FACTOR 2 and bacteriophage T4 anti-sigma factor AsiA. This pioneering study establishes the basis for future implementation of plastid optogenetics to regulate organelle responses upon exposure to specific light spectra.
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Affiliation(s)
- Luca Piccinini
- Plantlab, Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa 56127, Italy
| | - Sergio Iacopino
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
| | - Stefano Cazzaniga
- Department of Biotechnology, University of Verona, Verona 37134, Italy
| | - Matteo Ballottari
- Department of Biotechnology, University of Verona, Verona 37134, Italy
| | - Beatrice Giuntoli
- Plantlab, Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa 56127, Italy
- Department of Biology, University of Pisa, Pisa 56126, Italy
| | - Francesco Licausi
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
- Department of Biology, University of Pisa, Pisa 56126, Italy
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7
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Piccinini L, Iacopino S, Cazzaniga S, Ballottari M, Giuntoli B, Licausi F. A synthetic switch based on orange carotenoid protein to control blue-green light responses in chloroplasts. PLANT PHYSIOLOGY 2022; 189:1153-1168. [PMID: 35289909 PMCID: PMC9157063 DOI: 10.1093/plphys/kiac122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 02/20/2022] [Indexed: 05/11/2023]
Abstract
Synthetic biology approaches to engineer light-responsive systems are widely used, but their applications in plants are still limited due to the interference with endogenous photoreceptors and the intrinsic requirement of light for photosynthesis. Cyanobacteria possess a family of soluble carotenoid-associated proteins named orange carotenoid proteins (OCPs) that, when activated by blue-green light, undergo a reversible conformational change that enables the photoprotection mechanism that occurs on the phycobilisome. Exploiting this system, we developed a chloroplast-localized synthetic photoswitch based on a protein complementation assay where two nanoluciferase fragments were fused to separate polypeptides corresponding to the OCP2 domains. Since Arabidopsis (Arabidopsis thaliana) does not possess the prosthetic group needed for the assembly of the OCP2 complex, we first implemented the carotenoid biosynthetic pathway with a bacterial β-carotene ketolase enzyme (crtW) to generate keto-carotenoid-producing plants. The photoswitch was tested and characterized in Arabidopsis protoplasts and stably transformed plants with experiments aimed to uncover its regulation by a range of light intensities, wavelengths, and its conversion dynamics. Finally, we applied the OCP-based photoswitch to control transcriptional responses in chloroplasts in response to green light illumination by fusing the two OCP fragments with the plastidial SIGMA FACTOR 2 and bacteriophage T4 anti-sigma factor AsiA. This pioneering study establishes the basis for future implementation of plastid optogenetics to regulate organelle responses upon exposure to specific light spectra.
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Affiliation(s)
- Luca Piccinini
- Plantlab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Pisa 56127, Italy
| | - Sergio Iacopino
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
| | - Stefano Cazzaniga
- Department of Biotechnology, University of Verona, Verona 37134, Italy
| | - Matteo Ballottari
- Department of Biotechnology, University of Verona, Verona 37134, Italy
| | - Beatrice Giuntoli
- Plantlab, Institute of Life Sciences, Scuola Superiore Sant’Anna, Pisa 56127, Italy
- Department of Biology, University of Pisa, Pisa 56126, Italy
| | - Francesco Licausi
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, UK
- Department of Biology, University of Pisa, Pisa 56126, Italy
- Author for correspondence:
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8
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Pivato M, Perozeni F, Licausi F, Cazzaniga S, Ballottari M. Heterologous expression of cyanobacterial Orange Carotenoid Protein (OCP2) as a soluble carrier of ketocarotenoids in Chlamydomonas reinhardtii. ALGAL RES 2021; 55:102255. [PMID: 33777686 PMCID: PMC7610433 DOI: 10.1016/j.algal.2021.102255] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Photosynthetic organisms evolved different mechanisms to protect themselves from high irradiances and photodamage. In cyanobacteria, the photoactive Orange Carotenoid-binding Protein (OCP) acts both as a light sensor and quencher of excitation energy. It binds keto-carotenoids and, when photoactivated, interacts with phyco-bilisomes, thermally dissipating the excitation energy absorbed by the latter, and acting as efficient singlet oxygen quencher. Here, we report the heterologous expression of an OCP2 protein from the thermophilic cyanobacterium Fischerella thermalis (FtOCP2) in the model organism for green algae, Chlamydomonas reinhardtii. Robust expression of FtOCP2 was obtained through a synthetic redesigning strategy for optimized expression of the transgene. FtOCP2 expression was achieved both in UV-mediated mutant 4 strain, previously selected for efficient transgene expression, and in a background strain previously engineered for constitutive expression of an endogenous β-carotene ketolase, normally poorly expressed in this species, resulting into astaxanthin and other ketocarotenoids accumulation. Recombinant FtOCP2 was successfully localized into the chloroplast. Upon purification it was possible to demonstrate the formation of holoproteins with different xanthophylls and keto-carotenoids bound, including astaxanthin. Moreover, isolated ketocarotenoid-binding FtOCP2 holoproteins conserved their photoconversion properties. Carotenoids bound to FtOCP2 were thus maintained in solution even in absence of organic solvent. The synthetic biology approach herein reported could thus be considered as a novel tool for improving the solubility of ketocarotenoids produced in green algae, by binding to water-soluble carotenoids binding proteins.
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9
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Emerging research in plant photosynthesis. Emerg Top Life Sci 2020; 4:137-150. [PMID: 32573736 DOI: 10.1042/etls20200035] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 12/27/2022]
Abstract
Photosynthesis involves capturing light energy and, most often, converting it to chemical energy stored as reduced carbon. It is the source of food, fuel, and fiber and there is a resurgent interest in basic research on photosynthesis. Plants make excellent use of visible light energy; leaves are ideally suited to optimize light use by having a large area per amount of material invested and also having leaf angles to optimize light utilization. It is thought that plants do not use green light but in fact they use green light better than blue light under some conditions. Leaves also have mechanisms to protect against excess light and how these work in a stochastic light environment is currently a very active area of current research. The speed at which photosynthesis can begin when leaves are first exposed to light and the speed of induction of protective mechanisms, as well as the speed at which protective mechanisms dissipate when light levels decline, have recently been explored. Research is also focused on reducing wasteful processes such as photorespiration, when oxygen instead of carbon dioxide is used. Some success has been reported in altering the path of carbon in photorespiration but on closer inspection there appears to be unforeseen effects contributing to the good news. The stoichiometry of interaction of light reactions with carbon metabolism is rigid and the time constants vary tremendously presenting large challenges to regulatory mechanisms. Regulatory mechanisms will be the topic of photosynthesis research for some time to come.
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Yang W, Wang F, Liu LN, Sui N. Responses of Membranes and the Photosynthetic Apparatus to Salt Stress in Cyanobacteria. FRONTIERS IN PLANT SCIENCE 2020; 11:713. [PMID: 32582247 PMCID: PMC7292030 DOI: 10.3389/fpls.2020.00713] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 05/05/2020] [Indexed: 05/02/2023]
Abstract
Cyanobacteria are autotrophs whose photosynthetic process is similar to that of higher plants, although the photosynthetic apparatus is slightly different. They have been widely used for decades as model systems for studying the principles of photosynthesis, especially the effects of environmental stress on photosynthetic activities. Salt stress, which is the most common abiotic stress in nature, combines ionic and osmotic stresses. High cellular ion concentrations and osmotic stress can alter normal metabolic processes and photosynthesis. Additionally, salt stress increases the intracellular reactive oxygen species (ROS) contents. Excessive amounts of ROS will damage the photosynthetic apparatus, inhibit the synthesis of photosystem-related proteins, including the D1 protein, and destroy the thylakoid membrane structure, leading to inhibited photosynthesis. In this review, we mainly introduce the effects of salt stress on the cyanobacterial membranes and photosynthetic apparatus. We also describe specific salt tolerance mechanisms. A thorough characterization of the responses of membranes and photosynthetic apparatus to salt stress may be relevant for increasing agricultural productivity.
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Affiliation(s)
- Wenjing Yang
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan, China
| | - Fang Wang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, China
| | - Lu-Ning Liu
- College of Marine Life Sciences, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Na Sui
- Shandong Provincial Key Laboratory of Plant Stress, College of Life Sciences, Shandong Normal University, Jinan, China
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
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11
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Slonimskiy YB, Maksimov EG, Sluchanko NN. Fluorescence recovery protein: a powerful yet underexplored regulator of photoprotection in cyanobacteria†. Photochem Photobiol Sci 2020; 19:763-775. [PMID: 33856677 DOI: 10.1039/d0pp00015a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 03/03/2020] [Indexed: 01/17/2023]
Abstract
Cyanobacteria utilize an elegant photoprotection mechanism mediated by the photoactive Orange Carotenoid Protein (OCP), which upon binding dissipates excess energy from light-harvesting complexes, phycobilisomes. The OCP activity is efficiently regulated by its partner, the Fluorescence Recovery Protein (FRP). FRP accelerates OCP conversion to the resting state, thus counteracting the OCP-mediated photoprotection. Behind the deceptive simplicity of such regulation is hidden a multistep process involving dramatic conformational rearrangements in OCP and FRP, the details of which became clearer only a decade after the FRP discovery. Yet many questions regarding the functioning of FRP have remained controversial. In this review, we summarize the current knowledge and understanding of the FRP role in cyanobacterial photoprotection as well as its evolutionary history that presumably lies far beyond cyanobacteria.
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Affiliation(s)
- Yury B Slonimskiy
- A.N. Bach Institute of Biochemistry, Federal Research Center of Biotechnology of the Russian Academy of Sciences, 119071, Moscow, Russian Federation
- M. V. Lomonosov Moscow State University, Department of Biochemistry, Faculty of Biology, 119991, Moscow, Russian Federation
| | - Eugene G Maksimov
- A.N. Bach Institute of Biochemistry, Federal Research Center of Biotechnology of the Russian Academy of Sciences, 119071, Moscow, Russian Federation
- M. V. Lomonosov Moscow State University, Department of Biophysics, Faculty of Biology, 119991, Moscow, Russian Federation
| | - Nikolai N Sluchanko
- A.N. Bach Institute of Biochemistry, Federal Research Center of Biotechnology of the Russian Academy of Sciences, 119071, Moscow, Russian Federation.
- M. V. Lomonosov Moscow State University, Department of Biophysics, Faculty of Biology, 119991, Moscow, Russian Federation.
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Kuznetsova V, Dominguez-Martin MA, Bao H, Gupta S, Sutter M, Kloz M, Rebarz M, Přeček M, Chen Y, Petzold CJ, Ralston CY, Kerfeld CA, Polívka T. Comparative ultrafast spectroscopy and structural analysis of OCP1 and OCP2 from Tolypothrix. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2020; 1861:148120. [PMID: 31734194 PMCID: PMC6943196 DOI: 10.1016/j.bbabio.2019.148120] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 10/09/2019] [Accepted: 11/04/2019] [Indexed: 01/12/2023]
Abstract
The orange carotenoid protein (OCP) is a structurally and functionally modular photoactive protein involved in cyanobacterial photoprotection. Recently, based on bioinformatic analysis and phylogenetic relationships, new families of OCP have been described, OCP2 and OCPx. The first characterization of the OCP2 showed both faster photoconversion and back-conversion, and lower fluorescence quenching of phycobilisomes relative to the well-characterized OCP1. Moreover, OCP2 is not regulated by the fluorescence recovery protein (FRP). In this work, we present a comprehensive study combining ultrafast spectroscopy and structural analysis to compare the photoactivation mechanisms of OCP1 and OCP2 from Tolypothrix PCC 7601. We show that despite significant differences in their functional characteristics, the spectroscopic properties of OCP1 and OCP2 are comparable. This indicates that the OCP functionality is not directly related to the spectroscopic properties of the bound carotenoid. In addition, the structural analysis by X-ray footprinting reveals that, overall, OCP1 and OCP2 have grossly the same photoactivation mechanism. However, the OCP2 is less reactive to radiolytic labeling, suggesting that the protein is less flexible than OCP1. This observation could explain fast photoconversion of OCP2.
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Affiliation(s)
- Valentyna Kuznetsova
- Institute of Physics, Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05 České Budějovice, Czech Republic
| | | | - Han Bao
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
| | - Sayan Gupta
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Markus Sutter
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Miroslav Kloz
- ELI Beamlines, Institute of Physics, Czech Academy of Sciences, Za Radnicí 835, 252 41 Dolní Břežany, Czech Republic
| | - Mateusz Rebarz
- ELI Beamlines, Institute of Physics, Czech Academy of Sciences, Za Radnicí 835, 252 41 Dolní Břežany, Czech Republic
| | - Martin Přeček
- ELI Beamlines, Institute of Physics, Czech Academy of Sciences, Za Radnicí 835, 252 41 Dolní Břežany, Czech Republic
| | - Yan Chen
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Christopher J Petzold
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Corie Y Ralston
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Tomáš Polívka
- Institute of Physics, Faculty of Science, University of South Bohemia, Branišovská 1760, 370 05 České Budějovice, Czech Republic.
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