1
|
Zhou LJ, Höppner A, Wang YQ, Hou JY, Scheer H, Zhao KH. Crystallographic and biochemical analyses of a far-red allophycocyanin to address the mechanism of the super-red-shift. PHOTOSYNTHESIS RESEARCH 2024:10.1007/s11120-023-01066-2. [PMID: 38182842 DOI: 10.1007/s11120-023-01066-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Accepted: 12/03/2023] [Indexed: 01/07/2024]
Abstract
Far-red absorbing allophycocyanins (APC), identified in cyanobacteria capable of FRL photoacclimation (FaRLiP) and low-light photoacclimation (LoLiP), absorb far-red light, functioning in energy transfer as light-harvesting proteins. We report an optimized method to obtain high purity far-red absorbing allophycocyanin B, AP-B2, of Chroococcidiopsis thermalis sp. PCC7203 by synthesis in Escherichia coli and an improved purification protocol. The crystal structure of the trimer, (PCB-ApcD5/PCB-ApcB2)3, has been resolved to 2.8 Å. The main difference to conventional APCs absorbing in the 650-670 nm range is a largely flat chromophore with the co-planarity extending, in particular, from rings BCD to ring A. This effectively extends the conjugation system of PCB and contributes to the super-red-shifted absorption of the α-subunit (λmax = 697 nm). On complexation with the β-subunit, it is even further red-shifted (λmax, absorption = 707 nm, λmax, emission = 721 nm). The relevance of ring A for this shift is supported by mutagenesis data. A variant of the α-subunit, I123M, has been generated that shows an intense FR-band already in the absence of the β-subunit, a possible model is discussed. Two additional mechanisms are known to red-shift the chromophore spectrum: lactam-lactim tautomerism and deprotonation of the chromophore that both mechanisms appear inconsistent with our data, leaving this question unresolved.
Collapse
Affiliation(s)
- Li-Juan Zhou
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, The People's Republic of China
| | - Astrid Höppner
- Center for Structural Studies, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Yi-Qing Wang
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, The People's Republic of China
| | - Jian-Yun Hou
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, The People's Republic of China
| | - Hugo Scheer
- Department Biologie I, Universität München, Menzinger Str. 67, 80638, Munich, Germany
| | - Kai-Hong Zhao
- National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, 430070, The People's Republic of China.
| |
Collapse
|
2
|
Fadini A, Hutchison CDM, Morozov D, Chang J, Maghlaoui K, Perrett S, Luo F, Kho JCX, Romei MG, Morgan RML, Orr CM, Cordon-Preciado V, Fujiwara T, Nuemket N, Tosha T, Tanaka R, Owada S, Tono K, Iwata S, Boxer SG, Groenhof G, Nango E, van Thor JJ. Serial Femtosecond Crystallography Reveals that Photoactivation in a Fluorescent Protein Proceeds via the Hula Twist Mechanism. J Am Chem Soc 2023. [PMID: 37418747 PMCID: PMC10375524 DOI: 10.1021/jacs.3c02313] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/09/2023]
Abstract
Chromophore cis/trans photoisomerization is a fundamental process in chemistry and in the activation of many photosensitive proteins. A major task is understanding the effect of the protein environment on the efficiency and direction of this reaction compared to what is observed in the gas and solution phases. In this study, we set out to visualize the hula twist (HT) mechanism in a fluorescent protein, which is hypothesized to be the preferred mechanism in a spatially constrained binding pocket. We use a chlorine substituent to break the twofold symmetry of the embedded phenolic group of the chromophore and unambiguously identify the HT primary photoproduct. Through serial femtosecond crystallography, we then track the photoreaction from femtoseconds to the microsecond regime. We observe signals for the photoisomerization of the chromophore as early as 300 fs, obtaining the first experimental structural evidence of the HT mechanism in a protein on its femtosecond-to-picosecond timescale. We are then able to follow how chromophore isomerization and twisting lead to secondary structure rearrangements of the protein β-barrel across the time window of our measurements.
Collapse
Affiliation(s)
- Alisia Fadini
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, U.K
| | - Christopher D M Hutchison
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, U.K
| | - Dmitry Morozov
- Nanoscience Center and Department of Chemistry, University of Jyväskylä, Jyväskylä 40014, Finland
| | - Jeffrey Chang
- Department of Physics, Stanford University, Stanford, California 94305, United States
| | - Karim Maghlaoui
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, U.K
| | - Samuel Perrett
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, U.K
| | - Fangjia Luo
- RIKEN Spring-8 Center, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5148, Japan
| | - Jeslyn C X Kho
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, U.K
| | - Matthew G Romei
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - R Marc L Morgan
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, U.K
| | - Christian M Orr
- Diamond Light Source Ltd, Harwell Science & Innovation Campus, Didcot OX11 0DE, U.K
| | - Violeta Cordon-Preciado
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, U.K
| | - Takaaki Fujiwara
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577, Japan
| | - Nipawan Nuemket
- RIKEN Spring-8 Center, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5148, Japan
- Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo, Kyoto 606-8501, Japan
| | - Takehiko Tosha
- RIKEN Spring-8 Center, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5148, Japan
| | - Rie Tanaka
- RIKEN Spring-8 Center, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5148, Japan
- Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo, Kyoto 606-8501, Japan
| | - Shigeki Owada
- RIKEN Spring-8 Center, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5148, Japan
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5198, Japan
| | - Kensuke Tono
- RIKEN Spring-8 Center, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5148, Japan
- Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5198, Japan
| | - So Iwata
- RIKEN Spring-8 Center, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5148, Japan
- Department of Cell Biology, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo, Kyoto 606-8501, Japan
| | - Steven G Boxer
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Gerrit Groenhof
- Nanoscience Center and Department of Chemistry, University of Jyväskylä, Jyväskylä 40014, Finland
| | - Eriko Nango
- RIKEN Spring-8 Center, 1-1-1 Kouto, Sayo, Sayo, Hyogo 679-5148, Japan
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577, Japan
| | - Jasper J van Thor
- Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London SW7 2AZ, U.K
| |
Collapse
|
3
|
Zhu YH, Liu XX, Fang Q, Liu XY, Fang WH, Cui G. Multiple Photoisomerization Pathways of the Green Fluorescent Protein Chromophore in a Reversibly Photoswitchable Fluorescent Protein: Insights from Quantum Mechanics/Molecular Mechanics Simulations. J Phys Chem Lett 2023; 14:2588-2598. [PMID: 36881005 DOI: 10.1021/acs.jpclett.3c00165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Herein, we have employed a combined CASPT2//CASSCF approach within the quantum mechanics/molecular mechanics (QM/MM) framework to explore the early time photoisomerization of rsEGFP2 starting from its two OFF trans states, i.e., Trans1 and Trans2. The results show similar vertical excitation energies to the S1 state in their Franck-Condon regions. Considering the clockwise and counterclockwise rotations of the C11-C9 bond, four pairs of the S1 excited-state minima and low-lying S1/S0 conical intersections were optimized, based on which we determined four S1 photoisomerization paths that are essentially barrierless to the relevant S1/S0 conical intersections leading to efficient excited-state deactivation to the S0 state. Most importantly, our work first identified multiple photoisomerization and excited-state decay paths, which must be seriously considered in the future. This work not only sheds significant light on the primary trans-cis photoisomerization of rsEGFP2 but also aids in the understanding of the microscopic mechanism of GFP-like RSFPs and the design of novel GFP-like fluorescent proteins.
Collapse
Affiliation(s)
- Yun-Hua Zhu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Xin-Xin Liu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Qiu Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Xiang-Yang Liu
- College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610068, China
| | - Wei-Hai Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| |
Collapse
|
5
|
Weik M, Domratcheva T. Insight into the structural dynamics of light sensitive proteins from time-resolved crystallography and quantum chemical calculations. Curr Opin Struct Biol 2022; 77:102496. [PMID: 36462226 DOI: 10.1016/j.sbi.2022.102496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 10/14/2022] [Accepted: 10/14/2022] [Indexed: 12/03/2022]
Abstract
The structural dynamics underlying molecular mechanisms of light-sensitive proteins can be studied by a variety of experimental and computational biophysical techniques. Here we review recent progress in combining time-resolved crystallography at X-ray free electron lasers and quantum chemical calculations to study structural changes in photoenzymes, photosynthetic proteins, photoreceptors, and photoswitchable fluorescent proteins following photoexcitation.
Collapse
Affiliation(s)
- Martin Weik
- Univ. Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, F-38044 Grenoble, France.
| | - Tatiana Domratcheva
- Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russia; Max-Planck-Institut für medizinische Forschung, Jahnstrasse 29, 69120 Heidelberg, Germany.
| |
Collapse
|