1
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Yang C, Kim TW, Kim Y, Choi J, Lee SJ, Ihee H. Kinetics of the E46Q mutant of photoactive yellow protein investigated by transient grating spectroscopy. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.03.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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2
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García-Prieto FF, Muñoz-Losa A, Fdez Galván I, Sánchez ML, Aguilar MA, Martín ME. QM/MM Study of Substituent and Solvent Effects on the Excited State Dynamics of the Photoactive Yellow Protein Chromophore. J Chem Theory Comput 2017; 13:737-748. [PMID: 28072537 DOI: 10.1021/acs.jctc.6b01069] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Substituent and solvent effects on the excited state dynamics of the Photoactive Yellow Protein chromophore are studied using the average solvent electrostatic potential from molecular dynamics (ASEP/MD) method. Four molecular models were considered: the ester and thioester derivatives of the p-coumaric acid anion and their methylated derivatives. We found that the solvent produces dramatic modifications on the free energy profile of the S1 state: 1) Two twisted structures that are minima in the gas phase could not be located in aqueous solution. 2) Conical intersections (CIs) associated with the rotation of the single bond adjacent to the phenyl group are found for the four derivatives in water solution but only for thio derivatives in the gas phase. 3) The relative stability of minima and CIs is reverted with respect to the gas phase values, affecting the prevalent de-excitation paths. As a consequence of these changes, three competitive de-excitation channels are open in aqueous solution: the fluorescence emission from a planar minimum on S1, the trans-cis photoisomerization through a CI that involves the rotation of the vinyl double bond, and the nonradiative, nonreactive, de-excitation through the CI associated with the rotation of the single bond adjacent to the phenyl group. In the gas phase, the minima are the structures with the lower energy, while in solution these are the conical intersections. In solution, the de-excitation prevalent path seems to be the photoisomerization for oxo compounds, while thio compounds return to the initial trans ground state without emission.
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Affiliation(s)
- Francisco F García-Prieto
- Área de Química Física, University of Extremadura , Avda. Elvas s/n, Edif. José Ma Viguera Lobo 3a planta, Badajoz, 06006 Spain
| | - Aurora Muñoz-Losa
- Área de Química Física, University of Extremadura , Avda. Elvas s/n, Edif. José Ma Viguera Lobo 3a planta, Badajoz, 06006 Spain
| | - Ignacio Fdez Galván
- Department of Chemistry-Ångström, The Theoretical Chemistry Programme, Uppsala University , Box 518, 751 20 Uppsala, Sweden
| | - M Luz Sánchez
- Área de Química Física, University of Extremadura , Avda. Elvas s/n, Edif. José Ma Viguera Lobo 3a planta, Badajoz, 06006 Spain
| | - Manuel A Aguilar
- Área de Química Física, University of Extremadura , Avda. Elvas s/n, Edif. José Ma Viguera Lobo 3a planta, Badajoz, 06006 Spain
| | - M Elena Martín
- Área de Química Física, University of Extremadura , Avda. Elvas s/n, Edif. José Ma Viguera Lobo 3a planta, Badajoz, 06006 Spain
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3
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Kim TW, Yang C, Kim Y, Kim JG, Kim J, Jung YO, Jun S, Lee SJ, Park S, Kosheleva I, Henning R, van Thor JJ, Ihee H. Combined probes of X-ray scattering and optical spectroscopy reveal how global conformational change is temporally and spatially linked to local structural perturbation in photoactive yellow protein. Phys Chem Chem Phys 2017; 18:8911-8919. [PMID: 26960811 DOI: 10.1039/c6cp00476h] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Real-time probing of structural transitions of a photoactive protein is challenging owing to the lack of a universal time-resolved technique that can probe the changes in both global conformation and light-absorbing chromophores of the protein. In this work, we combine time-resolved X-ray solution scattering (TRXSS) and transient absorption (TA) spectroscopy to investigate how the global conformational changes involved in the photoinduced signal transduction of photoactive yellow protein (PYP) is temporally and spatially related to the local structural change around the light-absorbing chromophore. In particular, we examine the role of internal proton transfer in developing a signaling state of PYP by employing its E46Q mutant (E46Q-PYP), where the internal proton transfer is inhibited by the replacement of a proton donor. The comparison of TRXSS and TA spectroscopy data directly reveals that the global conformational change of the protein, which is probed by TRXSS, is temporally delayed by tens of microseconds from the local structural change of the chromophore, which is probed by TA spectroscopy. The molecular shape of the signaling state reconstructed from the TRXSS curves directly visualizes the three-dimensional conformations of protein intermediates and reveals that the smaller structural change in E46Q-PYP than in wild-type PYP suggested by previous studies is manifested in terms of much smaller protrusion, confirming that the signaling state of E46Q-PYP is only partially developed compared with that of wild-type PYP. This finding provides direct evidence of how the environmental change in the vicinity of the chromophore alters the conformational change of the entire protein matrix.
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Affiliation(s)
- Tae Wu Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 305-701, Korea
| | - Cheolhee Yang
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 305-701, Korea
| | - Youngmin Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 305-701, Korea
| | - Jong Goo Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 305-701, Korea
| | - Jeongho Kim
- Department of Chemistry, Inha University, Incheon 402-751, Korea
| | - Yang Ouk Jung
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 305-701, Korea
| | - Sunhong Jun
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 305-701, Korea
| | - Sang Jin Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 305-701, Korea
| | - Sungjun Park
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 305-701, Korea
| | - Irina Kosheleva
- Center for Advanced Radiation Sources, The University of Chicago, Chicago IL 60637, USA
| | - Robert Henning
- Center for Advanced Radiation Sources, The University of Chicago, Chicago IL 60637, USA
| | - Jasper J van Thor
- Division of Molecular Biosciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Hyotcherl Ihee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon, 305-701, Korea
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4
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Wei L, Wang H, Chen X, Fang W, Wang H. A comprehensive study of isomerization and protonation reactions in the photocycle of the photoactive yellow protein. Phys Chem Chem Phys 2014; 16:25263-72. [DOI: 10.1039/c4cp03495c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A comprehensive picture of the overall photocycle was obtained to reveal a wide range of structural signals in the photoactive yellow protein.
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Affiliation(s)
- Lili Wei
- Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education
- Department of Chemistry
- Beijing Normal University
- Beijing, China
| | - Hongjuan Wang
- Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education
- Department of Chemistry
- Beijing Normal University
- Beijing, China
| | - Xuebo Chen
- Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education
- Department of Chemistry
- Beijing Normal University
- Beijing, China
| | - Weihai Fang
- Key Laboratory of Theoretical and Computational Photochemistry of Ministry of Education
- Department of Chemistry
- Beijing Normal University
- Beijing, China
| | - Haobin Wang
- Department of Chemistry and Biochemistry
- New Mexico State University
- Las Cruces, USA
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5
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Jung YO, Lee JH, Kim J, Schmidt M, Moffat K, Srajer V, Ihee H. Volume-conserving trans-cis isomerization pathways in photoactive yellow protein visualized by picosecond X-ray crystallography. Nat Chem 2013; 5:212-20. [PMID: 23422563 PMCID: PMC3579544 DOI: 10.1038/nchem.1565] [Citation(s) in RCA: 144] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 12/19/2012] [Indexed: 12/23/2022]
Abstract
Trans-to-cis isomerization, the key reaction in photoactive proteins, usually cannot occur through the standard one-bond-flip mechanism. Owing to spatial constraints imposed by a protein environment, isomerization probably proceeds through a volume-conserving mechanism in which highly choreographed atomic motions are expected, the details of which have not yet been observed directly. Here we employ time-resolved X-ray crystallography to visualize structurally the isomerization of the p-coumaric acid chromophore in photoactive yellow protein with a time resolution of 100 ps and a spatial resolution of 1.6 Å. The structure of the earliest intermediate (I(T)) resembles a highly strained transition state in which the torsion angle is located halfway between the trans- and cis-isomers. The reaction trajectory of I(T) bifurcates into two structurally distinct cis intermediates via hula-twist and bicycle-pedal pathways. The bifurcating reaction pathways can be controlled by weakening the hydrogen bond between the chromophore and an adjacent residue through E46Q mutation, which switches off the bicycle-pedal pathway.
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Affiliation(s)
- Yang Ouk Jung
- Center for Nanomaterials and Chemical Reactions, Institute for Basic Science, Daejeon 305-701, Republic of Korea
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6
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Hellingwerf KJ, Hendriks J, Gensch T. On the Configurational and Conformational Changes in Photoactive Yellow Protein that Leads to Signal Generation in Ectothiorhodospira halophila. J Biol Phys 2013; 28:395-412. [PMID: 23345784 DOI: 10.1023/a:1020360505111] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Photoactive Yellow Protein (PYP), a phototaxis photoreceptor from Ectothiorhodospira halophila, is a small water-soluble protein that iscrystallisable and excellently photo-stable. It can be activated with light(λ(max)= 446 nm), to enter a series of transientintermediates that jointly form the photocycle of this photosensor protein.The most stable of these transient states is the signalling state forphototaxis, pB.The spatial structure of the ground state of PYP, pG and the spectralproperties of the photocycle intermediates have been very well resolved.Owing to its excellent chemical- and photochemical stability, also the spatialstructure of its photocycle intermediates has been characterised with X-raydiffraction and multinuclear NMR spectroscopy. Surprisingly, the resultsobtained showed that their structure is dependent on the molecular contextin which they are formed. Therefore, a large range of diffraction-,scattering- and spectroscopic techniques is now being employed to resolvein detail the dynamical changes of the structure of PYP while it progressesthrough its photocycle. This approach has led to considerable progress,although some techniques still result in mutually inconsistent conclusionsregarding aspects of the structure of particular intermediates.Recently, significant progress has also been made with simulations withmolecular dynamics analyses of the initial events that occur in PYP uponphoto activation. The great challenge in this field is to eventually obtainagreement between predicted dynamical alterations in PYP structure, asobtained with the MD approach and the actually measured dynamicalchanges in its structure as evolving during photocycle progression.
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7
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Nakamura R, Hamada N, Abe K, Yoshizawa M. Ultrafast hydrogen-bonding dynamics in the electronic excited state of photoactive yellow protein revealed by femtosecond stimulated Raman spectroscopy. J Phys Chem B 2012; 116:14768-75. [PMID: 23210980 DOI: 10.1021/jp308433a] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ultrafast structural dynamics in the electronic excited state of photoactive yellow protein (PYP) is studied by femtosecond stimulated Raman spectroscopy. Stimulated Raman spectra in the electronic excited state, S(1), can be obtained by using a Raman pump pulse in resonance with the S(1)-S(0) transition. This is confirmed by comparing the experimental results with numerical calculations based on the density matrix treatment. We also investigate the hydrogen-bonding network surrounding the wild-type (WT)-PYP chromophore in the ground and excited states by comparing its stimulated Raman spectra with those of the E46Q-PYP mutant. We focus on the relative intensity of the Raman band at 1555 cm(-1), which includes both vinyl bond C═C stretching and ring vibrations and is sensitive to the hydrogen-bonding network around the phenolic oxygen of the chromophore. The relative intensity for the WT-PYP decreases after actinic excitation within the 150 fs time resolution and reaches a similar intensity to that for E46Q-PYP. These observations indicate that the WT-PYP hydrogen-bonding network is immediately rearranged in the electronic excited state to form a structure similar to that of E46Q-PYP.
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Affiliation(s)
- Ryosuke Nakamura
- Science and Technology Entrepreneurship Laboratory, Osaka University, Suita, Osaka, Japan.
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8
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Lincoln CN, Fitzpatrick AE, van Thor JJ. Photoisomerisation quantum yield and non-linear cross-sections with femtosecond excitation of the photoactive yellow protein. Phys Chem Chem Phys 2012; 14:15752-64. [PMID: 23090503 DOI: 10.1039/c2cp41718a] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The quantum yield of photoisomerisation of the photoactive yellow protein (PYP) strongly depends on peak power and wavelength with femtosecond optical excitation. Using systematic power titrations and addition of second order dispersion resulting in 140, 300 and 600 fs pulse durations, the one and multi-photon cross-sections at 400, 450 and 490 nm have been assessed from transient absorption spectroscopy and additionally the Z-scan technique. Applying a target model that incorporates photoselection theory, estimates for the cross-sections for stimulated emission and absorption of the first excited state, the amount of ultrafast internal conversion and the underlying species associated dynamics have been determined. The final quantum yields for photoisomerisation were found to be 0.06, 0.14-0.19 and 0.02 for excitation wavelengths 400, 450 and 490 nm and found to increase with increasing pulse durations. Transient absorption measurements and Z-scan measurements at 450 nm, coinciding with the maximum wavelength of the ground state absorption, indicate that the photochemical quantum yield is intrinsically limited by an ultrafast internal conversion reaction as well as by stimulated emission cross-section. With excitation at 400 nm photoisomerisation quantum yield is further significantly limited by competing multi-photon excitation into excited state absorption at 385 nm previously proposed to result in photoionisation. With excitation at 490 nm the photoisomerisation quantum yield is predominantly limited further by the significantly higher stimulated emission cross-section compared to ground state cross-section as well as multi-photon processes. In addition to photoionisation, a second product of multi-photon excitation is identified and characterised by an induced absorption at 500 nm and a time constant of 2 ps for relaxation. With power densities up to 138 GW cm(-2) the measurements have not provided indication for coherent multi-photon absorption of PYP. In the saturation regime with 450 nm excitation, the limit for the photoisomerisation quantum yield was found to be 0.14-0.19 and the excited state absorption cross-section 6.1 × 10(-17) cm(2) or 0.36 times the ground state cross-section of 1.68 × 10(-16) cm(2) per molecule. This places a fundamental restriction on the maximum populations and sample penetration that may be achieved for instance in femtosecond pump-probe experiments with molecular crystals of PYP.
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Affiliation(s)
- Craig N Lincoln
- Imperial College London, Division of Molecular Biosciences, South Kensington campus, SW7 2AZ, London, UK
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9
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Losi A, Gensch T, van der Horst MA, Hellingwerf KJ, Braslavsky SE. Hydrogen-bond network probed by time-resolved optoacoustic spectroscopy: photoactive yellow protein and the effect of E46Q and E46A mutations. Phys Chem Chem Phys 2009; 7:2229-36. [PMID: 19791418 DOI: 10.1039/b419079c] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The enthalpy and structural volume changes (delta Hi and delta Vi) produced upon photoinduced formation and decay of the red-shifted intermediate (pR = I1) in the photoactive yellow protein (WT-PYP) from Halorhodospira halophila and the mutated E46Q-PYP and E46A-PYP, were determined by laser-induced optoacoustic spectroscopy (LIOAS) using the two-temperatures method, at pH 8.5. These mutations alter the hydrogen bond between the phenolate oxygen of the chromophore and the residue at position 46. Hydrogen bonding is still possible in E46Q-PYP via the delta-NH2 group of glutamine, whereas it is no longer possible with the methyl group of alanine in E46A-PYP. In all three proteins, pR decays within hundreds of ns to micros into the next intermediate, pR'. The delta H values for the formation of pR (delta H pR) and for its decay into pR'(delta H pR-->pR') are negligibly affected by the E46Q and the E46A substitution. In all three proteins the large delta H pR value drives the photocycle. Whereas delta V pR is a similar contraction of ca. 15 ml mol(-1) for E46Q-PYP and WT-PYP, attributed to strengthening the hydrogen bond network (between 4 and 5 hydrogen bonds) inside the protein chromophore cavity, an expansion is observed for E46A-PYP, indicating just an enlargement of the chromophore cavity upon chromophore isomerization. The results are discussed in the light of the recent time-resolved room temperature, crystallographic studies with WT-PYP and E46Q-PYP. Formation of pR' is somewhat slower for E46Q-PYP and much slower for E46A-PYP. The structural volume change for this transition, delta V pR-->pR', is relatively small and positive for WT-PYP, slightly larger for E46Q-PYP, and definitely larger for the hydrogen-bond lacking E46A-PYP. This indicates a larger entropic change for this transition in E46A-PYP, reflected in the large pre-exponential factor for the pR to pR' decay rate constant determined in the 5-30 degrees C temperature range. This decay also shows an activation entropy that compensates the larger activation energy in E46A-PYP, as compared to the values for WT-PYP and E46Q-PYP.
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Affiliation(s)
- Aba Losi
- Max-Planck-Institut für Bioanorganische Chemie (formerly Strahlenchemie), Postfach 101365, D-45413 Mülheim an der Ruhr, Germany
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10
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Kühn O, Wöste L. Biological systems: Applications and perspectives. ANALYSIS AND CONTROL OF ULTRAFAST PHOTOINDUCED REACTIONS 2007. [PMCID: PMC7122019 DOI: 10.1007/978-3-540-68038-3_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Oliver Kühn
- Institut f. Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, D-14195 Berlin, Germany
| | - Ludger Wöste
- Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany
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11
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Changenet-Barret P, Plaza P, Martin MM, Chosrowjan H, Taniguchi S, Mataga N, Imamoto Y, Kataoka M. Role of arginine 52 on the primary photoinduced events in the PYP photocycle. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2006.12.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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12
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Espagne A, Paik DH, Changenet-Barret P, Plaza P, Martin MM, Zewail AH. Ultrafast light-induced response of photoactive yellow protein chromophore analogues. Photochem Photobiol Sci 2007; 6:780-7. [PMID: 17609772 DOI: 10.1039/b700927e] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The fluorescence decays of several analogues of the photoactive yellow protein (PYP) chromophore in aqueous solution have been measured by femtosecond fluorescence up-conversion and the corresponding time-resolved fluorescence spectra have been reconstructed. The native chromophore of PYP is a thioester derivative of p-coumaric acid in its trans deprotonated form. Fluorescence kinetics are reported for a thioester phenyl analogue and for two analogues where the thioester group has been changed to amide and carboxylate groups. The kinetics are compared to those we previously reported for the analogues bearing ketone and ester groups. The fluorescence decays of the full series are found to lie in the 1-10 ps range depending on the electron-acceptor character of the substituent, in good agreement with the excited-state relaxation kinetics extracted from transient absorption measurements. Steady-state photolysis is also examined and found to depend strongly on the nature of the substituent. While it has been shown that the ultrafast light-induced response of the chromophore in PYP is controlled by the properties of the protein nanospace, the present results demonstrate that, in solution, the relaxation dynamics and pathway of the chromophore is controlled by its electron donor-acceptor structure: structures of stronger electron donor-acceptor character lead to faster decays and less photoisomerisation.
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Affiliation(s)
- Agathe Espagne
- UMR CNRS-ENS 8640 PASTEUR, Département de Chimie, Ecole Normale Supérieure, 24 rue Lhomond, 75005, Paris, France
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Abstract
The photoactive yellow protein (PYP) is the photoreceptor protein responsible for initiating the blue-light repellent response of the Halorhodospira halophila bacterium. Optical excitation of the intrinsic chromophore in PYP, p-coumaric acid, leads to the initiation of a photocycle that comprises several distinct intermediates. The dynamical processes responsible for the initiation of the PYP photocycle have been explored with several time-resolved techniques, which include ultrafast electronic and vibrational spectroscopies. Ultrafast electronic spectroscopies, such as pump-visible probe, pump-dump-visible probe, and fluorescence upconversion, are useful in identifying the timescales and connectivity of the transient intermediates, while ultrafast vibrational spectroscopies link these intermediates to dynamic structures. Herein, we present the use of these techniques for exploring the initial dynamics of PYP, and show how these techniques provide the basis for understanding the complex relationship between protein and chromophore, which ultimately results in biological function.
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Affiliation(s)
- Delmar S Larsen
- Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
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14
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Ihee H, Rajagopal S, Srajer V, Pahl R, Anderson S, Schmidt M, Schotte F, Anfinrud PA, Wulff M, Moffat K. Visualizing reaction pathways in photoactive yellow protein from nanoseconds to seconds. Proc Natl Acad Sci U S A 2005; 102:7145-50. [PMID: 15870207 PMCID: PMC1088170 DOI: 10.1073/pnas.0409035102] [Citation(s) in RCA: 202] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2004] [Indexed: 11/18/2022] Open
Abstract
Determining 3D intermediate structures during the biological action of proteins in real time under ambient conditions is essential for understanding how proteins function. Here we use time-resolved Laue crystallography to extract short-lived intermediate structures and thereby unveil signal transduction in the blue light photoreceptor photoactive yellow protein (PYP) from Halorhodospira halophila. By analyzing a comprehensive set of Laue data during the PYP photocycle (forty-seven time points from one nanosecond to one second), we track all atoms in PYP during its photocycle and directly observe how absorption of a blue light photon by its p-coumaric acid chromophore triggers a reversible photocycle. We identify a complex chemical mechanism characterized by five distinct structural intermediates. Structural changes at the chromophore in the early, red-shifted intermediates are transduced to the exterior of the protein in the late, blue-shifted intermediates through an initial "volume-conserving" isomerization of the chromophore and the progressive disruption of hydrogen bonds between the chromophore and its surrounding binding pocket. These results yield a comprehensive view of the PYP photocycle when seen in the light of previous biophysical studies on the system.
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Affiliation(s)
- Hyotcherl Ihee
- Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, South Korea.
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15
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Vengris M, van der Horst MA, Zgrablic G, van Stokkum IHM, Haacke S, Chergui M, Hellingwerf KJ, van Grondelle R, Larsen DS. Contrasting the excited-state dynamics of the photoactive yellow protein chromophore: protein versus solvent environments. Biophys J 2005; 87:1848-57. [PMID: 15345563 PMCID: PMC1304589 DOI: 10.1529/biophysj.104.043224] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Wavelength- and time-resolved fluorescence experiments have been performed on the photoactive yellow protein, the E46Q mutant, the hybrids of these proteins containing a nonisomerizing "locked" chromophore, and the native and locked chromophores in aqueous solution. The ultrafast dynamics of these six systems is compared and spectral signatures of isomerization and solvation are discussed. We find that the ultrafast red-shifting of fluorescence is associated mostly with solvation dynamics, whereas isomerization manifests itself as quenching of fluorescence. The observed multiexponential quenching of the protein samples differs from the single-exponential lifetimes of the chromophores in solution. The locked chromophore in the protein environment decays faster than in solution. This is due to additional channels of excited-state energy dissipation via the covalent and hydrogen bonds with the protein environment. The observed large dispersion of quenching timescales observed in the protein samples that contain the native pigment favors both an inhomogeneous model and an excited-state barrier for isomerization.
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Affiliation(s)
- Mikas Vengris
- Faculty of Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
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16
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Yamada A, Ishikura T, Yamato T. Direct measure of functional importance visualized atom-by-atom for photoactive yellow protein: Application to photoisomerization reaction. Proteins 2004; 55:1070-7. [PMID: 15146504 DOI: 10.1002/prot.20063] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Photoreceptor proteins serve as efficient nano-machines for the photoenergy conversion and the photosignal transduction of living organisms. For instance, the photoactive yellow protein derived from a halophilic bacterium has the p-coumaric acid chromophore, which undergoes an ultrafast photoisomerization reaction after light illumination. To understand the structure-function relationship at the atomic level, we used a computational method to find functionally important atoms for the photoisomerization reaction of the photoactive yellow protein. In the present study, a "direct" measure of the functional significance was quantitatively evaluated for each atom by calculating the partial atomic driving force for the photoisomerization reaction. As a result, we revealed the reaction mechanism in which the specific role of each functionally important atom has been well characterized in a systematic manner. In addition, we observed that this mechanism is strongly conserved during the thermal fluctuation of the photoactive yellow protein. We compared the experimental data of fluorescence decay constant of several different mutants and the present analysis. As a result, we found that the reaction rate constant is decreased when a large positive driving force is missing.
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Affiliation(s)
- Atsushi Yamada
- Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya, Japan
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Thompson MJ, Bashford D, Noodleman L, Getzoff ED. Photoisomerization and proton transfer in photoactive yellow protein. J Am Chem Soc 2003; 125:8186-94. [PMID: 12837088 DOI: 10.1021/ja0294461] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The photoactive yellow protein (PYP) is a bacterial photosensor containing a para-coumaryl thioester chromophore that absorbs blue light, initiating a photocycle involving a series of conformational changes. Here, we present computational studies to resolve uncertainties and controversies concerning the correspondence between atomic structures and spectroscopic measurements on early photocycle intermediates. The initial nanoseconds of the PYP photocycle are examined using time-dependent density functional theory (TDDFT) to calculate the energy profiles for chromophore photoisomerization and proton transfer, and to calculate excitation energies to identify photocycle intermediates. The calculated potential energy surface for photoisomerization matches key, experimentally determined, spectral parameters. The calculated excitation energy of the photocycle intermediate cryogenically trapped in a crystal structure by Genick et al. [Genick, U. K.; Soltis, S. M.; Kuhn, P.; Canestrelli, I. L.; Getzoff, E. D. Nature 1998, 392, 206-209] supports its assignment to the PYP(B) (I(0)) intermediate. Differences between the time-resolved room temperature (298 K) spectrum of the PYP(B) intermediate and its low temperature (77 K) absorbance are attributed to a predominantly deprotonated chromophore in the former and protonated chromophore in the latter. This contrasts with the widely held belief that chromophore protonation does not occur until after the PYP(L) (I(1) or pR) intermediate. The structure of the chromophore in the PYP(L) intermediate is determined computationally and shown to be deprotonated, in agreement with experiment. Calculations based on our PYP(B) and PYP(L) models lead to insights concerning the PYP(BL) intermediate, observed only at low temperature. The results suggest that the proton is more mobile between Glu46 and the chromophore than previously realized. The findings presented here provide an example of the insights that theoretical studies can contribute to a unified analysis of experimental structures and spectra.
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Affiliation(s)
- Michael J Thompson
- Department of Molecular Biology, MB4, Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Torrey Pines Rd., La Jolla, CA 92037, USA
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18
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Cusanovich MA, Meyer TE. Photoactive yellow protein: a prototypic PAS domain sensory protein and development of a common signaling mechanism. Biochemistry 2003; 42:4759-70. [PMID: 12718516 DOI: 10.1021/bi020690e] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michael A Cusanovich
- Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, Arizona 85721, USA.
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Premvardhan LL, van der Horst MA, Hellingwerf KJ, van Grondelle R. Stark spectroscopy on photoactive yellow protein, E46Q, and a nonisomerizing derivative, probes photo-induced charge motion. Biophys J 2003; 84:3226-39. [PMID: 12719252 PMCID: PMC1302883 DOI: 10.1016/s0006-3495(03)70047-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
The change in the electrostatic properties on excitation of the cofactor of wild-type photoactive yellow protein (WT-PYP) have been directly determined using Stark-effect spectroscopy. We find that, instantaneously on photon absorption, there is a large change in the permanent dipole moment, /Delta(-->)mu/, (26 Debye) and in the polarizability, (-)Deltaalpha, (1000 A(3)). We expect such a large degree of charge motion to have a significant impact on the photocycle that is associated with the important blue-light negative phototactic response of Halorhodospira halophila. Furthermore, changing E46 to Q in WT-PYP does not significantly alter its electrostatic properties, whereas, altering the chromophore to prevent it from undergoing trans-cis isomerization results in a significant diminution of /Delta(-->)mu/ and (-)Deltaalpha. We propose that the enormous charge motion that occurs on excitation of 4-hydroxycinnamyl thioester, the chromophore in WT-PYP, plays a crucial role in initiating the photocycle by translocation of the negative charge, localized on the phenolate oxygen in the ground state, across the chromophore. We hypothesize that this charge motion would consequently increase the flexibility of the thioester tail thereby decreasing the activation barrier for the rotation of this moiety in the excited state.
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Affiliation(s)
- L L Premvardhan
- Department of Biophysics and Physics of Complex Systems, Division of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, de Boelelaan, 1081, 1081 HV Amsterdam, The Netherlands.
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20
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Hellingwerf KJ, Hendriks J, Gensch T. Photoactive Yellow Protein, A New Type of Photoreceptor Protein: Will This “Yellow Lab” Bring Us Where We Want to Go? J Phys Chem A 2003. [DOI: 10.1021/jp027005y] [Citation(s) in RCA: 248] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Klaas J. Hellingwerf
- Laboratory for Microbiology, Swammerdam Institute for Life Sciences (SILS), BioCentrum, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, and Institute of Biological Information Processing 1, Research Centre Jülich, D-52425 Jülich, Germany
| | - Johnny Hendriks
- Laboratory for Microbiology, Swammerdam Institute for Life Sciences (SILS), BioCentrum, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, and Institute of Biological Information Processing 1, Research Centre Jülich, D-52425 Jülich, Germany
| | - Thomas Gensch
- Laboratory for Microbiology, Swammerdam Institute for Life Sciences (SILS), BioCentrum, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands, and Institute of Biological Information Processing 1, Research Centre Jülich, D-52425 Jülich, Germany
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21
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Gensch T, Gradinaru C, van Stokkum I, Hendriks J, Hellingwerf K, van Grondelle R. The primary photoreaction of photoactive yellow protein (PYP): anisotropy changes and excitation wavelength dependence. Chem Phys Lett 2002. [DOI: 10.1016/s0009-2614(02)00344-5] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Imamoto Y, Mihara K, Tokunaga F, Kataoka M. Spectroscopic characterization of the photocycle intermediates of photoactive yellow protein. Biochemistry 2001; 40:14336-43. [PMID: 11724545 DOI: 10.1021/bi010468u] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The absorption spectra of photocycle intermediates of photoactive yellow protein mutants were compared with those of the corresponding intermediates of wild type to probe which amino acid residues interact with the chromophore in the intermediate states. B and H intermediates were produced by irradiation and trapped at 80 K, and L intermediates at 193 K. The absorption spectra of these intermediates produced from R52Q were identical to those from wild type, whereas those from E46Q and T50V were 7-15 nm red-shifted as those in the dark states. The absorption spectra of M intermediates were measured by flash photolysis at room temperature. Those of Y42F, T50V, and R52Q were identical to that of wild type, whereas that of E46Q was 11 nm red-shifted. Assuming that the intermediates of mutants have a structure comparable to that of wild type, these findings suggest the following: Glu46 interacts with the chromophore throughout the photocycle, interaction between the chromophore and Thr50 as well as Tyr42 is lost upon the formation of M intermediate, and Arg52 never interacts with the chromophore directly. The hydrogen-bonding network around the phenolic oxygen of the chromophore would be thus maintained until L intermediate decays, and the global conformational change would take place by the loss of the hydrogen bond between the chromophore and Tyr42. This model conflicts with some of the results of previous crystallographic studies, suggesting that the reaction mechanism in the crystal may be different from that in solution.
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Affiliation(s)
- Y Imamoto
- Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0101, Japan.
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Devanathan S, Lin S, Cusanovich MA, Woodbury N, Tollin G. Early photocycle kinetic behavior of the E46A and Y42F mutants of photoactive yellow protein: femtosecond spectroscopy. Biophys J 2001; 81:2314-9. [PMID: 11566800 PMCID: PMC1301701 DOI: 10.1016/s0006-3495(01)75877-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In the photoactive yellow protein, PYP, both Glu46 and Tyr42 form hydrogen bonds to the phenolic OH group of the p-hydroxycinnamoyl chromophore. Previous work on replacement of the carboxyl group of Glu46 by an amide group (Glu46Gln) has shown that changing the nature of this hydrogen bond has a minimal effect on the rate constant for the formation of the first intermediate (I(0)) and on the excited state lifetime, whereas the rate constants for the formation of the second (I(0)( not equal)) and third (I(1)) intermediates were increased by factors of approximately 30 and 5, respectively. In the present experiments, two additional mutants (Glu46Ala and Tyr42Phe) have been studied. These two mutants are shown to behave kinetically very similarly to one another. In both cases, the rate constant for I(0) formation is decreased by a factor of approximately 2, with little or no effect on the photochemical yield as a consequence of a compensating increase in the excited state lifetime. Although we are unable to resolve the rate constant for the formation of the second intermediate from that of the first intermediate, the rate constant for the formation of the third intermediate is increased by a factor of approximately 100. The structural implications of these results are discussed.
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Affiliation(s)
- S Devanathan
- Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, Arizona 85721, USA
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Imamoto Y, Kataoka M, Tokunaga F, Asahi T, Masuhara H. Primary Photoreaction of Photoactive Yellow Protein Studied by Subpicosecond−Nanosecond Spectroscopy. Biochemistry 2001; 40:6047-52. [PMID: 11352740 DOI: 10.1021/bi002437p] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The primary photochemical event of photoactive yellow protein (PYP) was studied by laser flash photolysis experiments on a subpicosecond-nanosecond time scale. PYP was excited by a 390-nm pulse, and the transient difference absorption spectra were recorded by a multichannel spectrometer for a more reliable spectral analysis than previously possible. Just after excitation, an absorbance decrease due to the stimulated emission at 500 nm and photoconversion of PYP at 450 nm were observed. The stimulated emission gradually shifted to 520 nm and was retained up to 4 ps. Then, the formation of a red-shifted intermediate with a broad absorption spectrum was observed from 20 ps to 1 ns. Another red-shifted intermediate with a narrow absorption spectrum was formed after 2 ns and was stable for at least 5 ns. The latter is therefore believed to correspond to I1 (PYP(L)), which has been detected on a nanosecond time scale or trapped at -80 degrees C. Singular value decomposition analysis demonstrated that the spectral shifts observed from 0.5 ps to 5 ns could be explained by two-component decay of excited state(s) and conversion from PYP(B) to PYP(L). The amount of PYP(L) at 5 ns was less than that of photoconverted PYP, suggesting the formation of another intermediate, PYP(H). In addition, the absorption spectra of these intermediates were calculated based on the proposed reaction scheme. Together, these results indicate that the photocycle of PYP at room temperature has a branched pathway in the early stage and is essentially similar to that observed under low-temperature spectroscopy.
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Affiliation(s)
- Y Imamoto
- Graduate School of Materials Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0101, Japan.
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Zhou Y, Ujj L, Meyer TE, Cusanovich MA, Atkinson GH. Photocycle Dynamics and Vibrational Spectroscopy of the E46Q Mutant of Photoactive Yellow Protein. J Phys Chem A 2001. [DOI: 10.1021/jp004575u] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yidong Zhou
- Department of Chemistry and Optical Science Center and Department of Biochemistry, University of Arizona, Tucson, Arizona 85721
| | - Laszlo Ujj
- Department of Chemistry and Optical Science Center and Department of Biochemistry, University of Arizona, Tucson, Arizona 85721
| | - T. E. Meyer
- Department of Chemistry and Optical Science Center and Department of Biochemistry, University of Arizona, Tucson, Arizona 85721
| | - M. A. Cusanovich
- Department of Chemistry and Optical Science Center and Department of Biochemistry, University of Arizona, Tucson, Arizona 85721
| | - G. H. Atkinson
- Department of Chemistry and Optical Science Center and Department of Biochemistry, University of Arizona, Tucson, Arizona 85721
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