1
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Gotthard G, Mous S, Weinert T, Maia RNA, James D, Dworkowski F, Gashi D, Furrer A, Ozerov D, Panepucci E, Wang M, Schertler GFX, Heberle J, Standfuss J, Nogly P. Capturing the blue-light activated state of the Phot-LOV1 domain from Chlamydomonas reinhardtii using time-resolved serial synchrotron crystallography. IUCRJ 2024; 11:792-808. [PMID: 39037420 PMCID: PMC11364019 DOI: 10.1107/s2052252524005608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 06/11/2024] [Indexed: 07/23/2024]
Abstract
Light-oxygen-voltage (LOV) domains are small photosensory flavoprotein modules that allow the conversion of external stimuli (sunlight) into intracellular signals responsible for various cell behaviors (e.g. phototropism and chloroplast relocation). This ability relies on the light-induced formation of a covalent thioether adduct between a flavin chromophore and a reactive cysteine from the protein environment, which triggers a cascade of structural changes that result in the activation of a serine/threonine (Ser/Thr) kinase. Recent developments in time-resolved crystallography may allow the activation cascade of the LOV domain to be observed in real time, which has been elusive. In this study, we report a robust protocol for the production and stable delivery of microcrystals of the LOV domain of phototropin Phot-1 from Chlamydomonas reinhardtii (CrPhotLOV1) with a high-viscosity injector for time-resolved serial synchrotron crystallography (TR-SSX). The detailed process covers all aspects, from sample optimization to data collection, which may serve as a guide for soluble protein preparation for TR-SSX. In addition, we show that the crystals obtained preserve the photoreactivity using infrared spectroscopy. Furthermore, the results of the TR-SSX experiment provide high-resolution insights into structural alterations of CrPhotLOV1 from Δt = 2.5 ms up to Δt = 95 ms post-photoactivation, including resolving the geometry of the thioether adduct and the C-terminal region implicated in the signal transduction process.
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Affiliation(s)
- Guillaume Gotthard
- Institute of Molecular Biology and Biophysics, Department of BiologyETH Zurich8093ZürichSwitzerland
- Laboratory of Biomolecular Research, Division of Biology and ChemistryPaul Scherrer Institute5232Villigen PSISwitzerland
| | - Sandra Mous
- Institute of Molecular Biology and Biophysics, Department of BiologyETH Zurich8093ZürichSwitzerland
| | - Tobias Weinert
- Laboratory of Biomolecular Research, Division of Biology and ChemistryPaul Scherrer Institute5232Villigen PSISwitzerland
| | - Raiza Nara Antonelli Maia
- Experimental Molecular Biophysics, Department of PhysicsFreie Universität BerlinArnimallee 1414195BerlinGermany
| | - Daniel James
- Laboratory of Biomolecular Research, Division of Biology and ChemistryPaul Scherrer Institute5232Villigen PSISwitzerland
| | - Florian Dworkowski
- Macromolecular Crystallography, Swiss Light SourcePaul Scherrer Institute5232Villigen PSISwitzerland
| | - Dardan Gashi
- Laboratory of Biomolecular Research, Division of Biology and ChemistryPaul Scherrer Institute5232Villigen PSISwitzerland
- Laboratory of Femtochemistry, Photon Science DivisionPaul Scherrer Institute5232Villigen PSISwitzerland
| | - Antonia Furrer
- Laboratory of Biomolecular Research, Division of Biology and ChemistryPaul Scherrer Institute5232Villigen PSISwitzerland
| | - Dmitry Ozerov
- Science ITPaul Scherrer Institute5232Villigen PSISwitzerland
| | - Ezequiel Panepucci
- Laboratory for Macromolecules and Bioimaging, Photon Science DivisionPaul Scherrer Institute5232Villigen PSISwitzerland
| | - Meitian Wang
- Laboratory for Macromolecules and Bioimaging, Photon Science DivisionPaul Scherrer Institute5232Villigen PSISwitzerland
| | - Gebhard F. X. Schertler
- Laboratory of Biomolecular Research, Division of Biology and ChemistryPaul Scherrer Institute5232Villigen PSISwitzerland
- Department of BiologyETH Zürich8093ZürichSwitzerland
| | - Joachim Heberle
- Experimental Molecular Biophysics, Department of PhysicsFreie Universität BerlinArnimallee 1414195BerlinGermany
| | - Joerg Standfuss
- Laboratory of Biomolecular Research, Division of Biology and ChemistryPaul Scherrer Institute5232Villigen PSISwitzerland
| | - Przemyslaw Nogly
- Institute of Molecular Biology and Biophysics, Department of BiologyETH Zurich8093ZürichSwitzerland
- Dioscuri Center For Structural Dynamics of Receptors, Faculty of Biochemistry, Biophysics and BiotechnologyJagiellonian University in Kraków30-387KrakówPoland
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2
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Kim C, Yun SR, Lee SJ, Kim SO, Lee H, Choi J, Kim JG, Kim TW, You S, Kosheleva I, Noh T, Baek J, Ihee H. Structural dynamics of protein-protein association involved in the light-induced transition of Avena sativa LOV2 protein. Nat Commun 2024; 15:6991. [PMID: 39143073 PMCID: PMC11324726 DOI: 10.1038/s41467-024-51461-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 08/07/2024] [Indexed: 08/16/2024] Open
Abstract
The Light-oxygen-voltage-sensing domain (LOV) superfamily, found in enzymes and signal transduction proteins, plays a crucial role in converting light signals into structural signals, mediating various biological mechanisms. While time-resolved spectroscopic studies have revealed the dynamics of the LOV-domain chromophore's electronic structures, understanding the structural changes in the protein moiety, particularly regarding light-induced dimerization, remains challenging. Here, we utilize time-resolved X-ray liquidography to capture the light-induced dimerization of Avena sativa LOV2. Our analysis unveils that dimerization occurs within milliseconds after the unfolding of the A'α and Jα helices in the microsecond time range. Notably, our findings suggest that protein-protein interactions (PPIs) among the β-scaffolds, mediated by helix unfolding, play a key role in dimerization. In this work, we offer structural insights into the dimerization of LOV2 proteins following structural changes in the A'α and Jα helices, as well as mechanistic insights into the protein-protein association process driven by PPIs.
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Affiliation(s)
- Changin Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - So Ri Yun
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Sang Jin Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Seong Ok Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Hyosub Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Jungkweon Choi
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Jong Goo Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Tae Wu Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Seyoung You
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Irina Kosheleva
- Center for Advanced Radiation Sources, The University of Chicago, Chicago, IL, 60637, USA
| | - Taeyoon Noh
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Jonghoon Baek
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea
| | - Hyotcherl Ihee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
- Center for Advanced Reaction Dynamics, Institute for Basic Science (IBS), Daejeon, 34141, Republic of Korea.
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3
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Arshi SA, Chauhan M, Sharma A. Disruption of the FMN-A524 interaction cascade and Glu513-induced collapse of the hydrophobic barrier promotes light-induced Jα-helix unfolding in AsLOV2. Biophys J 2023; 122:4670-4685. [PMID: 37978801 PMCID: PMC10754690 DOI: 10.1016/j.bpj.2023.11.011] [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: 04/28/2023] [Revised: 10/10/2023] [Accepted: 11/14/2023] [Indexed: 11/19/2023] Open
Abstract
The C-terminal Jα-helix of the Avena sativa's Light Oxygen and Voltage (AsLOV2) protein, unfolds on exposure to blue light. This characteristic seeks relevance in applications related to engineering novel biological photoswitches. Using molecular dynamics simulations and the Markov state modeling (MSM) approach we provide the mechanism that explains the stepwise unfolding of the Jα-helix. The unfolding was resolved into seven steps represented by the structurally distinguishable states distributed over the initiation and the post initiation phases. Whereas, the initiation phase occurs due to the collapse of the interaction cascade FMN-Q513-N492-L480-W491-Q479-V520-A524, the onset of the post initiation phase is marked by breaking of the hydrophobic interactions between the Jα-helix and the Iβ-strand. This study indicates that the displacement of N492 out of the FMN binding pocket, not necessarily requiring Q513, is essential for the initiation of the Jα-helix unfolding. Rather, the structural reorientation of Q513 activates the protein to cross the hydrophobic barrier and enter the post initiation phase. Similarly, the structural deviations in N482, rather than its integral role in unfolding, could enhance the unfolding rates. Furthermore, the MSM studies on the wild-type and the Q513 mutant, provide the spatiotemporal roadmap that lay out the possible pathways of structural transition between the dark and the light states of the protein. Overall, the study provides insights useful to enhance the performance of AsLOV2-based photoswitches.
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Affiliation(s)
- Syeda Amna Arshi
- Multidisciplinary Centre for Advance Research and Studies, Jamia Millia Islamia, New Delhi, India
| | - Manisha Chauhan
- Multidisciplinary Centre for Advance Research and Studies, Jamia Millia Islamia, New Delhi, India
| | - Amit Sharma
- Multidisciplinary Centre for Advance Research and Studies, Jamia Millia Islamia, New Delhi, India.
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4
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Pounot K, Schirò G, Levantino M. Tracking the structural dynamics of proteins with time-resolved X-ray solution scattering. Curr Opin Struct Biol 2023; 82:102661. [PMID: 37536065 DOI: 10.1016/j.sbi.2023.102661] [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: 02/23/2023] [Revised: 05/03/2023] [Accepted: 06/29/2023] [Indexed: 08/05/2023]
Abstract
Relevant events during protein function such as ligand binding/release and interaction with substrates or with light are often accompanied by out-of-equilibrium structural dynamics. Time-resolved experimental techniques have been developed to follow protein structural changes as they happen in real time after a given reaction-triggering event. Time-resolved X-ray solution scattering is a promising approach that bears structural sensitivity with temporal resolution in the femto-to-millisecond time range, depending on the X-ray source characteristics and the triggering method. Here we present the basic principles of the technique together with a description of the most relevant results recently published and a discussion on the computational methods currently developed to achieve a structural interpretation of the time-resolved X-ray solution scattering experimental data.
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Affiliation(s)
- Kevin Pounot
- ESRF - The European Synchrotron, 71 Avenue des Martyrs, CS40220, 38043 Grenoble Cedex 9, France
| | - Giorgio Schirò
- Univ. Grenoble Alpes, CNRS, CEA, IBS, F-38000 Grenoble, France.
| | - Matteo Levantino
- ESRF - The European Synchrotron, 71 Avenue des Martyrs, CS40220, 38043 Grenoble Cedex 9, France.
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5
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Shankar U, Lenka SK, Leigh Ackland M, Callahan DL. Review of the structures and functions of algal photoreceptors to optimize bioproduct production with novel bioreactor designs for strain improvement. Biotechnol Bioeng 2022; 119:2031-2045. [PMID: 35441370 DOI: 10.1002/bit.28116] [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: 11/19/2021] [Revised: 04/15/2022] [Accepted: 04/15/2022] [Indexed: 11/11/2022]
Abstract
Microalgae are important renewable feedstock to produce biodiesel and high-value chemicals. Different wavelengths of light influence the growth and metabolic activities of algae. Recent research has identified the light-sensing proteins called photoreceptors that respond to blue or red light. Structural elucidations of algal photoreceptors have gained momentum over recent years. These include channelrhodopsins, PHOT proteins, animal-like cryptochromes, blue-light sensors utilizing flavin-adenine dinucleotide (BLUF) proteins. Pulsing light has also been investigated as a means to optimize energy inputs into bioreactors. This review summarizes the current structural and functional basis of photoreceptor modulation to optimize the growth, production of carotenoids and other high-value metabolites from microalgae. The review also encompasses novel photobioreactor designs that implement different light regimes including light wavelengths and time to optimize algal growth and desired metabolite profiles for high-value products. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Uttara Shankar
- TERI-Deakin Nanobiotechnology Centre, The Energy and Resources Institute, Gurugram, Haryana, 122001, India.,Deakin University, Geelong, Australia. School of Life and Environmental Sciences, (Burwood Campus), Centre for Cellular and Molecular biology. 221 Burwood Highway, Burwood, VIC, 3125, Australia
| | - Sangram K Lenka
- TERI-Deakin Nanobiotechnology Centre, The Energy and Resources Institute, Gurugram, Haryana, 122001, India.,Gujarat Biotechnology University, Gandhinagar, Gujarat, 382355, India
| | - M Leigh Ackland
- Deakin University, Geelong, Australia. School of Life and Environmental Sciences, (Burwood Campus), Centre for Cellular and Molecular biology. 221 Burwood Highway, Burwood, VIC, 3125, Australia
| | - Damien L Callahan
- Deakin University, Geelong, Australia. School of Life and Environmental Sciences, (Burwood Campus), Centre for Cellular and Molecular biology. 221 Burwood Highway, Burwood, VIC, 3125, Australia
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6
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Orädd F, Ravishankar H, Goodman J, Rogne P, Backman L, Duelli A, Nors Pedersen M, Levantino M, Wulff M, Wolf-Watz M, Andersson M. Tracking the ATP-binding response in adenylate kinase in real time. SCIENCE ADVANCES 2021; 7:eabi5514. [PMID: 34788091 PMCID: PMC8597995 DOI: 10.1126/sciadv.abi5514] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 09/27/2021] [Indexed: 05/25/2023]
Abstract
The biological function of proteins is critically dependent on dynamics inherent to the native structure. Such structural dynamics obey a predefined order and temporal timing to execute the specific reaction. Determination of the cooperativity of key structural rearrangements requires monitoring protein reactions in real time. In this work, we used time-resolved x-ray solution scattering (TR-XSS) to visualize structural changes in the Escherichia coli adenylate kinase (AdK) enzyme upon laser-induced activation of a protected ATP substrate. A 4.3-ms transient intermediate showed partial closing of both the ATP- and AMP-binding domains, which indicates a cooperative closing mechanism. The ATP-binding domain also showed local unfolding and breaking of an Arg131-Asp146 salt bridge. Nuclear magnetic resonance spectroscopy data identified similar unfolding in an Arg131Ala AdK mutant, which refolded in a closed, substrate-binding conformation. The observed structural dynamics agree with a “cracking mechanism” proposed to underlie global structural transformation, such as allostery, in proteins.
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Affiliation(s)
- Fredrik Orädd
- Department of Chemistry, Umeå University, Linnaeus Väg 10, 901 87 Umeå, Sweden
| | - Harsha Ravishankar
- Department of Chemistry, Umeå University, Linnaeus Väg 10, 901 87 Umeå, Sweden
| | - Jack Goodman
- Department of Chemistry, Umeå University, Linnaeus Väg 10, 901 87 Umeå, Sweden
| | - Per Rogne
- Department of Chemistry, Umeå University, Linnaeus Väg 10, 901 87 Umeå, Sweden
| | - Lars Backman
- Department of Chemistry, Umeå University, Linnaeus Väg 10, 901 87 Umeå, Sweden
| | - Annette Duelli
- Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, 2200 Copenhagen, Denmark
| | - Martin Nors Pedersen
- ESRF—The European Synchrotron, 71 Avenue des Martyrs, CS40220, 38043 Grenoble, Cedex 9, France
| | - Matteo Levantino
- ESRF—The European Synchrotron, 71 Avenue des Martyrs, CS40220, 38043 Grenoble, Cedex 9, France
| | - Michael Wulff
- ESRF—The European Synchrotron, 71 Avenue des Martyrs, CS40220, 38043 Grenoble, Cedex 9, France
| | - Magnus Wolf-Watz
- Department of Chemistry, Umeå University, Linnaeus Väg 10, 901 87 Umeå, Sweden
| | - Magnus Andersson
- Department of Chemistry, Umeå University, Linnaeus Väg 10, 901 87 Umeå, Sweden
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7
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Andrikopoulos PC, Chaudhari AS, Liu Y, Konold PE, Kennis JTM, Schneider B, Fuertes G. QM calculations predict the energetics and infrared spectra of transient glutamine isomers in LOV photoreceptors. Phys Chem Chem Phys 2021; 23:13934-13950. [PMID: 34142688 PMCID: PMC8246142 DOI: 10.1039/d1cp00447f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 06/04/2021] [Indexed: 11/21/2022]
Abstract
Photosensory receptors containing the flavin-binding light-oxygen-voltage (LOV) domain are modular proteins that fulfil a variety of biological functions ranging from gene expression to phototropism. The LOV photocycle is initiated by blue-light and involves a cascade of intermediate species, including an electronically excited triplet state, that leads to covalent bond formation between the flavin mononucleotide (FMN) chromophore and a nearby cysteine residue. Subsequent conformational changes in the polypeptide chain arise due to the remodelling of the hydrogen bond network in the cofactor binding pocket, whereby a conserved glutamine residue plays a key role in coupling FMN photochemistry with LOV photobiology. Although the dark-to-light transition of LOV photosensors has been previously addressed by spectroscopy and computational approaches, the mechanistic basis of the underlying reactions is still not well understood. Here we present a detailed computational study of three distinct LOV domains: EL222 from Erythrobacter litoralis, AsLOV2 from the second LOV domain of Avena sativa phototropin 1, and RsLOV from Rhodobacter sphaeroides LOV protein. Extended protein-chromophore models containing all known crucial residues involved in the initial steps (femtosecond-to-microsecond) of the photocycle were employed. Energies and rotational barriers were calculated for possible rotamers and tautomers of the critical glutamine side chain, which allowed us to postulate the most energetically favoured glutamine orientation for each LOV domain along the assumed reaction path. In turn, for each evolving species, infrared difference spectra were constructed and compared to experimental EL222 and AsLOV2 transient infrared spectra, the former from original work presented here and the latter from the literature. The good agreement between theory and experiment permitted the assignment of the majority of observed bands, notably the ∼1635 cm-1 transient of the adduct state to the carbonyl of the glutamine side chain after rotation. Moreover, both the energetic and spectroscopic approaches converge in suggesting a facile glutamine flip at the adduct intermediate for EL222 and more so for AsLOV2, while for RsLOV the glutamine keeps its initial configuration. Additionally, the computed infrared shifts of the glutamine and interacting residues could guide experimental research addressing early events of signal transduction in LOV proteins.
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Affiliation(s)
- Prokopis C Andrikopoulos
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, CZ-252 50 Vestec, Czechia.
| | - Aditya S Chaudhari
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, CZ-252 50 Vestec, Czechia.
| | - Yingliang Liu
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, CZ-252 50 Vestec, Czechia.
| | - Patrick E Konold
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, 1081 De Boelelaan, 1081HV Amsterdam, The Netherlands
| | - John T M Kennis
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, 1081 De Boelelaan, 1081HV Amsterdam, The Netherlands
| | - Bohdan Schneider
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, CZ-252 50 Vestec, Czechia.
| | - Gustavo Fuertes
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Průmyslová 595, CZ-252 50 Vestec, Czechia.
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Poddar H, Heyes DJ, Schirò G, Weik M, Leys D, Scrutton NS. A guide to time-resolved structural analysis of light-activated proteins. FEBS J 2021; 289:576-595. [PMID: 33864718 DOI: 10.1111/febs.15880] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/03/2021] [Accepted: 04/13/2021] [Indexed: 01/08/2023]
Abstract
Dynamical changes in protein structures are essential for protein function and occur over femtoseconds to seconds timescales. X-ray free electron lasers have facilitated investigations of structural dynamics in proteins with unprecedented temporal and spatial resolution. Light-activated proteins are attractive targets for time-resolved structural studies, as the reaction chemistry and associated protein structural changes can be triggered by short laser pulses. Proteins with different light-absorbing centres have evolved to detect light and harness photon energy to bring about downstream chemical and biological output responses. Following light absorption, rapid chemical/small-scale structural changes are typically localised around the chromophore. These localised changes are followed by larger structural changes propagated throughout the photoreceptor/photocatalyst that enables the desired chemical and/or biological output response. Time-resolved serial femtosecond crystallography (SFX) and solution scattering techniques enable direct visualisation of early chemical change in light-activated proteins on timescales previously inaccessible, whereas scattering gives access to slower timescales associated with more global structural change. Here, we review how advances in time-resolved SFX and solution scattering techniques have uncovered mechanisms of photochemistry and its coupling to output responses. We also provide a prospective on how these time-resolved structural approaches might impact on other photoreceptors/photoenzymes that have not yet been studied by these methods.
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Affiliation(s)
- Harshwardhan Poddar
- Manchester Institute of Biotechnology, Department of Chemistry, University of Manchester, UK
| | - Derren J Heyes
- Manchester Institute of Biotechnology, Department of Chemistry, University of Manchester, UK
| | - Giorgio Schirò
- Institut de Biologie Structurale, Univ. Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Martin Weik
- Institut de Biologie Structurale, Univ. Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - David Leys
- Manchester Institute of Biotechnology, Department of Chemistry, University of Manchester, UK
| | - Nigel S Scrutton
- Manchester Institute of Biotechnology, Department of Chemistry, University of Manchester, UK
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9
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Hart JE, Gardner KH. Lighting the way: Recent insights into the structure and regulation of phototropin blue light receptors. J Biol Chem 2021; 296:100594. [PMID: 33781746 PMCID: PMC8086140 DOI: 10.1016/j.jbc.2021.100594] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 02/06/2023] Open
Abstract
The phototropins (phots) are light-activated kinases that are critical for plant physiology and the many diverse optogenetic tools that they have inspired. Phototropins combine two blue-light-sensing Light-Oxygen-Voltage (LOV) domains (LOV1 and LOV2) and a C-terminal serine/threonine kinase domain, using the LOV domains to control the catalytic activity of the kinase. While much is known about the structure and photochemistry of the light-perceiving LOV domains, particularly in how activation of the LOV2 domain triggers the unfolding of alpha helices that communicate the light signal to the kinase domain, many questions about phot structure and mechanism remain. Recent studies have made progress addressing these questions by utilizing small-angle X-ray scattering (SAXS) and other biophysical approaches to study multidomain phots from Chlamydomonas and Arabidopsis, leading to models where the domains have an extended linear arrangement, with the regulatory LOV2 domain contacting the kinase domain N-lobe. We discuss this and other advances that have improved structural and mechanistic understanding of phot regulation in this review, along with the challenges that will have to be overcome to obtain high-resolution structural information on these exciting photoreceptors. Such information will be essential to advancing fundamental understanding of plant physiology while enabling engineering efforts at both the whole plant and molecular levels.
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Affiliation(s)
- Jaynee E Hart
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, New York, USA
| | - Kevin H Gardner
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, New York, USA; Department of Chemistry and Biochemistry, City College of New York, New York, USA; PhD Programs in Biochemistry, Chemistry, and Biology, Graduate Center, City University of New York, New York, USA.
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