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Likkei K, Moldenhauer M, Tavraz NN, Egorkin NA, Slonimskiy YB, Maksimov EG, Sluchanko NN, Friedrich T. Elements of the C-terminal tail of a C-terminal domain homolog of the Orange Carotenoid Protein determining xanthophyll uptake from liposomes. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2024; 1865:149043. [PMID: 38522658 DOI: 10.1016/j.bbabio.2024.149043] [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: 12/06/2023] [Revised: 03/07/2024] [Accepted: 03/09/2024] [Indexed: 03/26/2024]
Abstract
Carotenoids perform multifaceted roles in life ranging from coloration over light harvesting to photoprotection. The Orange Carotenoid Protein (OCP), a light-driven photoswitch involved in cyanobacterial photoprotection, accommodates a ketocarotenoid vital for its function. OCP extracts its ketocarotenoid directly from membranes, or accepts it from homologs of its C-terminal domain (CTDH). The CTDH from Anabaena (AnaCTDH) was shown to be important for carotenoid transfer and delivery from/to membranes. The C-terminal tail of AnaCTDH is a critical structural element likely serving as a gatekeeper and facilitator of carotenoid uptake from membranes. We investigated the impact of amino acid substitutions within the AnaCTDH-CTT on echinenone and canthaxanthin uptake from DOPC and DMPG liposomes. The transfer rate was uniformly reduced for substitutions of Arg-137 and Arg-138 to Gln or Ala, and depended on the lipid type, indicating a weaker interaction particularly with the lipid head group. Our results further suggest that Glu-132 has a membrane-anchoring effect on the PC lipids, specifically at the choline motif as inferred from the strongly different effects of the CTT variants on the extraction from the two liposome types. The substitution of Pro-130 by Gly suggests that the CTT is perpendicular to both the membrane and the main AnaCTDH protein during carotenoid extraction. Finally, the simultaneous mutation of Leu-133, Leu-134 and Leu-136 for alanines showed that the hydrophobicity of the CTT is crucial for carotenoid uptake. Since some substitutions accelerated carotenoid transfer into AnaCTDH while others slowed it down, carotenoprotein properties can be engineered toward the requirements of applications.
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Affiliation(s)
- Kristina Likkei
- 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
| | - Neslihan N Tavraz
- Technische Universität Berlin, Institute of Chemistry, PC 14, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - Nikita A Egorkin
- Federal Research Center of Biotechnology of the Russian Academy of Sciences, A.N. Bach Institute of Biochemistry, Leninsky Prospect 33-1, Moscow 119071, Russian Federation; Lomonosov Moscow State University, Faculty of Biology, Leninskie Gory 1-12, Moscow 119991, Russian Federation
| | - Yury B Slonimskiy
- Federal Research Center of Biotechnology of the Russian Academy of Sciences, A.N. Bach Institute of Biochemistry, Leninsky Prospect 33-1, Moscow 119071, Russian Federation
| | - Eugene G Maksimov
- Lomonosov Moscow State University, Faculty of Biology, Leninskie Gory 1-12, Moscow 119991, Russian Federation
| | - Nikolai N Sluchanko
- Federal Research Center of Biotechnology of the Russian Academy of Sciences, A.N. Bach Institute of Biochemistry, Leninsky Prospect 33-1, Moscow 119071, Russian Federation
| | - Thomas Friedrich
- Technische Universität Berlin, Institute of Chemistry, PC 14, Straße des 17. Juni 135, 10623 Berlin, Germany.
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2
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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 2024:168625. [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] [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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3
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Arcidiacono A, Accomasso D, Cupellini L, Mennucci B. How orange carotenoid protein controls the excited state dynamics of canthaxanthin. Chem Sci 2023; 14:11158-11169. [PMID: 37860660 PMCID: PMC10583711 DOI: 10.1039/d3sc02662k] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 09/21/2023] [Indexed: 10/21/2023] Open
Abstract
Orange Carotenoid Protein (OCP) is a ketocarotenoid-binding protein essential for photoprotection in cyanobacteria. The main steps of the photoactivated conversion which converts OCP from its resting state to the active one have been extensively investigated. However, the initial photochemical event in the ketocarotenoid which triggers the large structural changes finally leading to the active state is still not understood. Here we employ QM/MM surface hopping nonadiabatic dynamics to investigate the excited-state decay of canthaxanthin in OCP, both in the ultrafast S2 to S1 internal conversion and the slower decay leading back to the ground state. For the former step we show the involvement of an additional excited state, which in the literature has been often named the SX state, and we characterize its nature. For the latter step, we reveal an excited state decay characterized by multiple timescales, which are related to the ground-state conformational heterogeneity of the ketocarotenoid. We assigned the slowly decaying population to the so-called S* state. Finally, we identify a minor decay pathway involving double-bond photoisomerization, which could be the initial trigger to photoactivation of OCP.
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Affiliation(s)
- Amanda Arcidiacono
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa Via G. Moruzzi 13 56124 Pisa Italy
| | - Davide Accomasso
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa Via G. Moruzzi 13 56124 Pisa Italy
| | - Lorenzo Cupellini
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa Via G. Moruzzi 13 56124 Pisa Italy
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa Via G. Moruzzi 13 56124 Pisa Italy
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4
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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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Yang YW, Liu K, Huang D, Yu C, Chen SZ, Chen M, Qiu BS. Functional specialization of expanded orange carotenoid protein paralogs in subaerial Nostoc species. PLANT PHYSIOLOGY 2023:kiad234. [PMID: 37070859 DOI: 10.1093/plphys/kiad234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 03/27/2023] [Accepted: 04/17/2023] [Indexed: 06/19/2023]
Abstract
Orange carotenoid protein (OCP) is a photoactive protein that participates in the photoprotection of cyanobacteria. There are two full-length OCP proteins, four N-terminal paralogs (helical carotenoid protein, HCP), and one C-terminal domain-like carotenoid protein (CCP) found in Nostoc flagelliforme, a desert cyanobacterium. All HCPs (HCP1-3 and HCP6) from N. flagelliforme demonstrated their excellent singlet oxygen quenching activities, in which HCP2 was the strongest singlet oxygen quencher compared with others. Two OCPs, OCPx1 and OCPx2, were not involved in singlet oxygen scavenging; instead, they functioned as phycobilisome fluorescence quenchers. The fast-acting OCPx1 showed more effective photoactivation and stronger phycobilisome fluorescence quenching compared to OCPx2, which behaved differently from all reported OCP paralogs. The resolved crystal structure and mutant analysis revealed that Trp111 and Met125 play essential roles in OCPx2, which is dominant and long-acting. The resolved crystal structure of OCPx2 is maintained in a monomer state and showed more flexible regulation in energy quenching activities compared with the packed oligomer of OCPx1. The recombinant apo-CCP obtained the carotenoid pigment from holo-HCPs and holo-OCPx1 of N. flagelliforme. No such carotenoid transferring processes were observed between apo-CCP and holo-OCPx2. The close phylogenetic relationship of OCP paralogs from subaerial Nostoc species indicates an adaptive evolution toward development of photoprotection: protecting cellular metabolism against singlet oxygen damage using HCPs and against excess energy captured by active phycobilisomes using two different working modes of OCPx.
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Affiliation(s)
- Yi-Wen Yang
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei 430079, China
- College of Pharmacy and Life Sciences, Jiujiang University, Jiujiang, Jiangxi 332000, China
| | - Ke Liu
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei 430079, China
| | - Da Huang
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei 430079, China
| | - Chen Yu
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei 430079, China
| | - Si-Zhuo Chen
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei 430079, China
| | - Min Chen
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia
| | - Bao-Sheng Qiu
- School of Life Sciences, and Hubei Key Laboratory of Genetic Regulation and Integrative Biology, Central China Normal University, Wuhan, Hubei 430079, China
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6
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Glotz G, Püschmann S, Haas M, Gescheidt G. Direct detection of photo-induced reactions by IR: from Brook rearrangement to photo-catalysis. Photochem Photobiol Sci 2023:10.1007/s43630-023-00406-4. [PMID: 36933157 DOI: 10.1007/s43630-023-00406-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 02/28/2023] [Indexed: 03/19/2023]
Abstract
In situ IR detection of photoreactions induced by the light of LEDs at appropriate wavelengths provides a simple, cost-effective, and versatile method to get insight into mechanistic details. In particular, conversions of functional groups can be selectively followed. Overlapping UV-Vis bands or fluorescence from the reactants and products and the incident light do not obstruct IR detection. Compared with in situ photo-NMR, our setup does not require tedious sample preparation (optical fibers) and offers a selective detection of reactions, even at positions where 1H-NMR lines overlap or 1H resonances are not clear-cut. We illustrate the applicability of our setup following the photo-Brook rearrangement of (adamant-1-yl-carbonyl)-tris(trimethylsilyl)silane, address photo-induced α-bond cleavage (1-hydroxycyclohexyl phenyl ketone), study photoreduction using tris(bipyridine)ruthenium(II), investigate photo-oxygenation of double bonds with molecular oxygen and the fluorescent 2,4,6-triphenylpyrylium photocatalyst, and address photo-polymerization. With the LED/FT-IR combination, reactions can be qualitatively followed in fluid solution, (highly) viscous environments, and in the solid state. Viscosity changes during the reaction (e.g., during a polymerization) do not obstruct the method.
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Affiliation(s)
- Gabriel Glotz
- Institute of Physical and Theoretical Chemistry, Graz University of Technology, Stremayrgasse 9/II, 8010, Graz, Austria.
| | - Sabrina Püschmann
- Institute of Inorganic Chemistry, Graz University of Technology, Stremayrgasse 9/IV, 8010, Graz, Austria
| | - Michael Haas
- Institute of Inorganic Chemistry, Graz University of Technology, Stremayrgasse 9/IV, 8010, Graz, Austria
| | - Georg Gescheidt
- Institute of Physical and Theoretical Chemistry, Graz University of Technology, Stremayrgasse 9/II, 8010, Graz, Austria
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7
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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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8
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Chukhutsina VU, Baxter JM, Fadini A, Morgan RM, Pope MA, Maghlaoui K, Orr CM, Wagner A, van Thor JJ. Light activation of Orange Carotenoid Protein reveals bicycle-pedal single-bond isomerization. Nat Commun 2022; 13:6420. [PMID: 36307413 PMCID: PMC9616832 DOI: 10.1038/s41467-022-34137-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 10/14/2022] [Indexed: 12/25/2022] Open
Abstract
Orange Carotenoid protein (OCP) is the only known photoreceptor which uses carotenoid for its activation. It is found exclusively in cyanobacteria, where it functions to control light-harvesting of the photosynthetic machinery. However, the photochemical reactions and structural dynamics of this unique photosensing process are not yet resolved. We present time-resolved crystal structures at second-to-minute delays under bright illumination, capturing the early photoproduct and structures of the subsequent reaction intermediates. The first stable photoproduct shows concerted isomerization of C9'-C8' and C7'-C6' single bonds in the bicycle-pedal (s-BP) manner and structural changes in the N-terminal domain with minute timescale kinetics. These are followed by a thermally-driven recovery of the s-BP isomer to the dark state carotenoid configuration. Structural changes propagate to the C-terminal domain, resulting, at later time, in the H-bond rupture of the carotenoid keto group with protein residues. Solution FTIR and UV/Vis spectroscopy support the single bond isomerization of the carotenoid in the s-BP manner and subsequent thermal structural reactions as the basis of OCP photoreception.
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Affiliation(s)
- Volha U. Chukhutsina
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, SW7 2AZ UK
| | - James M. Baxter
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, SW7 2AZ UK
| | - Alisia Fadini
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, SW7 2AZ UK
| | - Rhodri M. Morgan
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, SW7 2AZ UK
| | - Matthew A. Pope
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, SW7 2AZ UK
| | - Karim Maghlaoui
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, SW7 2AZ UK
| | - Christian M. Orr
- grid.18785.330000 0004 1764 0696Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE UK
| | - Armin Wagner
- grid.18785.330000 0004 1764 0696Diamond Light Source, Harwell Science and Innovation Campus, Didcot, OX11 0DE UK
| | - Jasper J. van Thor
- grid.7445.20000 0001 2113 8111Department of Life Sciences, Imperial College London, London, SW7 2AZ UK
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9
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Wilson A, Andreeva EA, Niziński S, Talbot L, Hartmann E, Schlichting I, Burdzinski G, Sliwa M, Kirilovsky D, Colletier JP. Structure-function-dynamics relationships in the peculiar Planktothrix PCC7805 OCP1: Impact of his-tagging and carotenoid type. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2022; 1863:148584. [PMID: 35752265 DOI: 10.1016/j.bbabio.2022.148584] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 05/31/2022] [Accepted: 06/07/2022] [Indexed: 06/15/2023]
Abstract
The orange carotenoid protein (OCP) is a photoactive protein involved in cyanobacterial photoprotection. Here, we report on the functional, spectral and structural characteristics of the peculiar Planktothrix PCC7805 OCP (Plankto-OCP). We show that this OCP variant is characterized by higher photoactivation and recovery rates, and a stronger energy-quenching activity, compared to other OCP studied thus far. We characterize the effect of the functionalizing carotenoid and of his-tagging on these reactions, and identify the time scales on which these modifications affect photoactivation. The presence of a his-tag at the C-terminus has a large influence on photoactivation, thermal recovery and PBS-fluorescence quenching, and likewise for the nature of the carotenoid that additionally affects the yield and characteristics of excited states and the ns-s dynamics of photoactivated OCP. By solving the structures of Plankto-OCP in the ECN- and CAN-functionalized states, each in two closely-related crystal forms, we further unveil the molecular breathing motions that animate Plankto-OCP at the monomer and dimer levels. We finally discuss the structural changes that could explain the peculiar properties of Plankto-OCP.
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Affiliation(s)
- Adjélé Wilson
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Elena A Andreeva
- Univ. Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, 38000 Grenoble, France; Max-Planck-Institut für medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Stanisław Niziński
- Univ. Lille, CNRS, UMR 8516, LASIRE, LAboratoire de Spectroscopie pour les Interactions, la Réactivité et l'Environnement, Lille 59000, France; Quantum Electronics Laboratory, Faculty of Physics, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 2, Poznan 61-614, Poland
| | - Léa Talbot
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Elisabeth Hartmann
- Max-Planck-Institut für medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Ilme Schlichting
- Max-Planck-Institut für medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany
| | - Gotard Burdzinski
- Quantum Electronics Laboratory, Faculty of Physics, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 2, Poznan 61-614, Poland
| | - Michel Sliwa
- Univ. Lille, CNRS, UMR 8516, LASIRE, LAboratoire de Spectroscopie pour les Interactions, la Réactivité et l'Environnement, Lille 59000, France.
| | - Diana Kirilovsky
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France.
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10
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Niziński S, Schlichting I, Colletier JP, Kirilovsky D, Burdzinski G, Sliwa M. Is orange carotenoid protein photoactivation a single-photon process? BIOPHYSICAL REPORTS 2022; 2:100072. [PMID: 36425326 PMCID: PMC9680785 DOI: 10.1016/j.bpr.2022.100072] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 08/17/2022] [Indexed: 06/16/2023]
Abstract
In all published photoactivation mechanisms of orange carotenoid protein (OCP), absorption of a single photon by the orange dark state starts a cascade of red-shifted OCP ground-state intermediates that subsequently decay within hundreds of milliseconds, resulting in the formation of the final red form OCPR, which is the biologically active form that plays a key role in cyanobacteria photoprotection. A major challenge in deducing the photoactivation mechanism is to create a uniform description explaining both single-pulse excitation experiments, involving single-photon absorption, and continuous light irradiation experiments, where the red-shifted OCP intermediate species may undergo re-excitation. We thus investigated photoactivation of Synechocystis OCP using stationary irradiation light with a biologically relevant photon flux density coupled with nanosecond laser pulse excitation. The kinetics of photoactivation upon continuous and nanosecond pulse irradiation light show that the OCPR formation quantum yield increases with photon flux density; thus, a simple single-photon model cannot describe the data recorded for OCP in vitro. The results strongly suggest a consecutive absorption of two photons involving a red intermediate with ≈100 millisecond lifetime. This intermediate is required in the photoactivation mechanism and formation of the red active form OCPR.
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Affiliation(s)
- Stanisław Niziński
- Quantum Electronics Laboratory, Faculty of Physics, Adam Mickiewicz University in Poznań, Poznan, Poland
- Univ. Lille, CNRS, UMR 8516 - LASIRE, Laboratoire Avancé de Spectroscopie pour les Interactions, la Réactivité et l’Environnement, Lille, France
| | - Ilme Schlichting
- Max-Planck-Institut für medizinische Forschung, Heidelberg, Germany
| | | | - Diana Kirilovsky
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Gotard Burdzinski
- Quantum Electronics Laboratory, Faculty of Physics, Adam Mickiewicz University in Poznań, Poznan, Poland
| | - Michel Sliwa
- Univ. Lille, CNRS, UMR 8516 - LASIRE, Laboratoire Avancé de Spectroscopie pour les Interactions, la Réactivité et l’Environnement, Lille, France
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11
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Oligomerization processes limit photoactivation and recovery of the Orange Carotenoid Protein. Biophys J 2022; 121:2849-2872. [PMID: 35794830 PMCID: PMC9388578 DOI: 10.1016/j.bpj.2022.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 05/17/2022] [Accepted: 07/01/2022] [Indexed: 11/23/2022] Open
Abstract
The Orange Carotenoid Protein (OCP) is a photoactive protein involved in cyanobacterial photoprotection, by quenching of the excess of light harvested energy. The photoactivation mechanism remains elusive, in part due to absence of data pertaining to the timescales over which protein structural changes take place. It also remains unclear whether or not oligomerization of the dark-adapted and light-adapted OCP could play a role in the regulation of its energy quenching activity. Here, we probed photo-induced structural changes in OCP by a combination of static and time-resolved X-ray scattering and steady-state and transient optical spectroscopy in the visible range. Our results suggest that oligomerization partakes in regulation of the OCP photocycle, with different oligomers slowing down the overall thermal recovery of the dark-adapted state of OCP. They furthermore reveal that upon non-photoproductive excitation, a numbed-state forms, which remains in a non-photoexcitable structural state for at least ∼0.5 μs after absorption of a first photon.
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12
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Sharawy M, Pigni NB, May ER, Gascón JA. A favorable path to domain separation in the orange carotenoid protein. Protein Sci 2022; 31:850-863. [PMID: 35000233 PMCID: PMC8927859 DOI: 10.1002/pro.4273] [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: 09/21/2021] [Revised: 12/24/2021] [Accepted: 01/03/2022] [Indexed: 11/10/2022]
Abstract
The orange carotenoid protein (OCP) is responsible for nonphotochemical quenching (NPQ) in cyanobacteria, a defense mechanism against potentially damaging effects of excess light conditions. This soluble two-domain protein undergoes profound conformational changes upon photoactivation, involving translocation of the ketocarotenoid inside the cavity followed by domain separation. Domain separation is a critical step in the photocycle of OCP because it exposes the N-terminal domain (NTD) to perform quenching of the phycobilisomes. Many details regarding the mechanism and energetics of OCP domain separation remain unknown. In this work, we apply metadynamics to elucidate the protein rearrangements that lead to the active, domain-separated, form of OCP. We find that translocation of the ketocarotenoid canthaxanthin has a profound effect on the energetic landscape and that domain separation only becomes favorable following translocation. We further explore, characterize, and validate the free energy surface (FES) using equilibrium simulations initiated from different states on the FES. Through pathway optimization methods, we characterize the most probable path to domain separation and reveal the barriers along that pathway. We find that the free energy barriers are relatively small (<5 kcal/mol), but the overall estimated kinetic rate is consistent with experimental measurements (>1 ms). Overall, our results provide detailed information on the requirement for canthaxanthin translocation to precede domain separation and an energetically feasible pathway to dissociation.
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Affiliation(s)
- Mahmoud Sharawy
- Department of Molecular and Cell BiologyUniversity of ConnecticutStorrsConnecticutUSA
| | - Natalia B. Pigni
- Department of ChemistryUniversity of ConnecticutStorrsConnecticutUSA
- Instituto de Ciencia y Tecnología de Alimentos Córdoba (ICYTAC‐CONICET)Ciudad UniversitariaCórdobaArgentina
| | - Eric R. May
- Department of Molecular and Cell BiologyUniversity of ConnecticutStorrsConnecticutUSA
| | - José A. Gascón
- Department of ChemistryUniversity of ConnecticutStorrsConnecticutUSA
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13
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An ultra-sensitive near-infrared fluorescent probe based on triphenylamine with high selectivity detecting the keratin. Anal Biochem 2022; 646:114638. [DOI: 10.1016/j.ab.2022.114638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/23/2022] [Accepted: 03/02/2022] [Indexed: 02/02/2023]
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14
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Time-resolved infrared absorption spectroscopy applied to photoinduced reactions: how and why. Photochem Photobiol Sci 2022; 21:557-584. [DOI: 10.1007/s43630-022-00180-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Accepted: 01/28/2022] [Indexed: 10/19/2022]
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15
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El Khoury Y, Le Breton G, Cunha AV, Jansen TLC, van Wilderen LJGW, Bredenbeck J. Lessons from combined experimental and theoretical examination of the FTIR and 2D-IR spectroelectrochemistry of the amide I region of cytochrome c. J Chem Phys 2021; 154:124201. [PMID: 33810651 DOI: 10.1063/5.0039969] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Amide I difference spectroscopy is widely used to investigate protein function and structure changes. In this article, we show that the common approach of assigning features in amide I difference signals to distinct secondary structure elements in many cases may not be justified. Evidence comes from Fourier transform infrared (FTIR) and 2D-IR spectroelectrochemistry of the protein cytochrome c in the amide I range, in combination with computational spectroscopy based on molecular dynamics (MD) simulations. This combination reveals that each secondary structure unit, such as an alpha-helix or a beta-sheet, exhibits broad overlapping contributions, usually spanning a large part of the amide I region, which in the case of difference absorption experiments (such as in FTIR spectroelectrochemistry) may lead to intensity-compensating and even sign-changing contributions. We use cytochrome c as the test case, as this small electron-transferring redox-active protein contains different kinds of secondary structure units. Upon switching its redox-state, the protein exhibits a different charge distribution while largely retaining its structural scaffold. Our theoretical analysis suggests that the change in charge distribution contributes to the spectral changes and that structural changes are small. However, in order to confidently interpret FTIR amide I difference signals in cytochrome c and proteins in general, MD simulations in combination with additional experimental approaches such as isotope labeling, the insertion of infrared labels to selectively probe local structural elements will be required. In case these data are not available, a critical assessment of previous interpretations of protein amide I 1D- and 2D-IR difference spectroscopy data is warranted.
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Affiliation(s)
- Youssef El Khoury
- Institut für Biophysik, Johann-Wolfgang-Goethe-Universität, Max-von-Laue-Strasse. 1, 60438 Frankfurt am Main, Germany
| | - Guillaume Le Breton
- University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Ana V Cunha
- University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Thomas L C Jansen
- University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Luuk J G W van Wilderen
- Institut für Biophysik, Johann-Wolfgang-Goethe-Universität, Max-von-Laue-Strasse. 1, 60438 Frankfurt am Main, Germany
| | - Jens Bredenbeck
- Institut für Biophysik, Johann-Wolfgang-Goethe-Universität, Max-von-Laue-Strasse. 1, 60438 Frankfurt am Main, Germany
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16
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Bondanza M, Cupellini L, Faccioli P, Mennucci B. Molecular Mechanisms of Activation in the Orange Carotenoid Protein Revealed by Molecular Dynamics. J Am Chem Soc 2020; 142:21829-21841. [PMID: 33332967 PMCID: PMC7775743 DOI: 10.1021/jacs.0c10461] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Light-harvesting
in photosynthesis is accompanied by photoprotective
processes. In cyanobacteria, the photoprotective role is played by
a specialized complex, the orange carotenoid protein, which is activated
by strong blue-green light. This photoactivation involves a unique
series of structural changes which terminate with an opening of the
complex into two separate domains, one of which acts as a quencher
for the light-harvesting complexes. Many experimental studies have
tried to reveal the molecular mechanisms through which the energy
absorbed by the carotenoid finally leads to the large conformational
change of the complex. Here, for the first time, these mechanisms
are revealed by simulating at the atomistic level the whole dynamics
of the complex through an effective combination of enhanced sampling
techniques. On the basis of our findings, we can conclude that the
carotenoid does not act as a spring that, releasing its internal strain,
induces the dissociation, as was previously proposed, but as a “latch”
locking together the two domains. The photochemically triggered displacement
of the carotenoid breaks this balance, allowing the complex to dissociate.
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Affiliation(s)
- Mattia Bondanza
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Lorenzo Cupellini
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
| | - Pietro Faccioli
- Physics Department, Trento University, Via Sommarive 14, 38128 Povo, Trento, Italy
| | - Benedetta Mennucci
- Dipartimento di Chimica e Chimica Industriale, University of Pisa, via G. Moruzzi 13, 56124 Pisa, Italy
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17
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Abstract
Infrared difference spectroscopy probes vibrational changes of proteins upon their perturbation. Compared with other spectroscopic methods, it stands out by its sensitivity to the protonation state, H-bonding, and the conformation of different groups in proteins, including the peptide backbone, amino acid side chains, internal water molecules, or cofactors. In particular, the detection of protonation and H-bonding changes in a time-resolved manner, not easily obtained by other techniques, is one of the most successful applications of IR difference spectroscopy. The present review deals with the use of perturbations designed to specifically change the protein between two (or more) functionally relevant states, a strategy often referred to as reaction-induced IR difference spectroscopy. In the first half of this contribution, I review the technique of reaction-induced IR difference spectroscopy of proteins, with special emphasis given to the preparation of suitable samples and their characterization, strategies for the perturbation of proteins, and methodologies for time-resolved measurements (from nanoseconds to minutes). The second half of this contribution focuses on the spectral interpretation. It starts by reviewing how changes in H-bonding, medium polarity, and vibrational coupling affect vibrational frequencies, intensities, and bandwidths. It is followed by band assignments, a crucial aspect mostly performed with the help of isotopic labeling and site-directed mutagenesis, and complemented by integration and interpretation of the results in the context of the studied protein, an aspect increasingly supported by spectral calculations. Selected examples from the literature, predominately but not exclusively from retinal proteins, are used to illustrate the topics covered in this review.
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18
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Bondanza M, Cupellini L, Lipparini F, Mennucci B. The Multiple Roles of the Protein in the Photoactivation of Orange Carotenoid Protein. Chem 2020. [DOI: 10.1016/j.chempr.2019.10.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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19
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Muzzopappa F, Kirilovsky D. Changing Color for Photoprotection: The Orange Carotenoid Protein. TRENDS IN PLANT SCIENCE 2020; 25:92-104. [PMID: 31679992 DOI: 10.1016/j.tplants.2019.09.013] [Citation(s) in RCA: 63] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 09/16/2019] [Accepted: 09/18/2019] [Indexed: 05/09/2023]
Abstract
Under high irradiance, light becomes dangerous for photosynthetic organisms and they must protect themselves. Cyanobacteria have developed a simple mechanism, involving a photoactive soluble carotenoid protein, the orange carotenoid protein (OCP), which increases thermal dissipation of excess energy by interacting with the cyanobacterial antenna, the phycobilisome. Here, we summarize our knowledge of the OCP-related photoprotective mechanism, including the remarkable progress that has been achieved in recent years on OCP photoactivation and interaction with phycobilisomes, as well as with the fluorescence recovery protein, which is necessary to end photoprotection. A recently discovered unique mechanism of carotenoid transfer between soluble proteins related to OCP is also described.
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Affiliation(s)
- Fernando Muzzopappa
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif sur Yvette, France
| | - Diana Kirilovsky
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, 91198 Gif sur Yvette, France.
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20
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Liu J, Lu Y, Hua W, Last RL. A New Light on Photosystem II Maintenance in Oxygenic Photosynthesis. FRONTIERS IN PLANT SCIENCE 2019; 10:975. [PMID: 31417592 PMCID: PMC6685048 DOI: 10.3389/fpls.2019.00975] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 07/11/2019] [Indexed: 05/19/2023]
Abstract
Life on earth is sustained by oxygenic photosynthesis, a process that converts solar energy, carbon dioxide, and water into chemical energy and biomass. Sunlight is essential for growth and productivity of photosynthetic organisms. However, exposure to an excessive amount of light adversely affects fitness due to photooxidative damage to the photosynthetic machinery, primarily to the reaction center of the oxygen-evolving photosystem II (PSII). Photosynthetic organisms have evolved diverse photoprotective and adaptive strategies to avoid, alleviate, and repair PSII damage caused by high-irradiance or fluctuating light. Rapid and harmless dissipation of excess absorbed light within antenna as heat, which is measured by chlorophyll fluorescence as non-photochemical quenching (NPQ), constitutes one of the most efficient protective strategies. In parallel, an elaborate repair system represents another efficient strategy to maintain PSII reaction centers in active states. This article reviews both the reaction center-based strategy for robust repair of photodamaged PSII and the antenna-based strategy for swift control of PSII light-harvesting (NPQ). We discuss evolutionarily and mechanistically diverse strategies used by photosynthetic organisms to maintain PSII function for growth and productivity under static high-irradiance light or fluctuating light environments. Knowledge of mechanisms underlying PSII maintenance would facilitate bioengineering photosynthesis to enhance agricultural productivity and sustainability to feed a growing world population amidst climate change.
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Affiliation(s)
- Jun Liu
- Department of Functional Genomics and Molecular Biology, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, China
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, United States
- *Correspondence: Jun Liu,
| | - Yan Lu
- Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, United States
| | - Wei Hua
- Department of Functional Genomics and Molecular Biology, Key Laboratory of Biology and Genetic Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan, China
- Wei Hua
| | - Robert L. Last
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, United States
- Department of Plant Biology, Michigan State University, East Lansing, MI, United States
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