1
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Schotte F, Cho HS, Dyda F, Anfinrud P. Watching a signaling protein function: What has been learned over four decades of time-resolved studies of photoactive yellow protein. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2024; 11:021303. [PMID: 38595979 PMCID: PMC11003764 DOI: 10.1063/4.0000241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/24/2023] [Accepted: 03/21/2024] [Indexed: 04/11/2024]
Abstract
Photoactive yellow protein (PYP) is a signaling protein whose internal p-coumaric acid chromophore undergoes reversible, light-induced trans-to-cis isomerization, which triggers a sequence of structural changes that ultimately lead to a signaling state. Since its discovery nearly 40 years ago, PYP has attracted much interest and has become one of the most extensively studied proteins found in nature. The method of time-resolved crystallography, pioneered by Keith Moffat, has successfully characterized intermediates in the PYP photocycle at near atomic resolution over 12 decades of time down to the sub-picosecond time scale, allowing one to stitch together a movie and literally watch a protein as it functions. But how close to reality is this movie? To address this question, results from numerous complementary time-resolved techniques including x-ray crystallography, x-ray scattering, and spectroscopy are discussed. Emerging from spectroscopic studies is a general consensus that three time constants are required to model the excited state relaxation, with a highly strained ground-state cis intermediate formed in less than 2.4 ps. Persistent strain drives the sequence of structural transitions that ultimately produce the signaling state. Crystal packing forces produce a restoring force that slows somewhat the rates of interconversion between the intermediates. Moreover, the solvent composition surrounding PYP can influence the number and structures of intermediates as well as the rates at which they interconvert. When chloride is present, the PYP photocycle in a crystal closely tracks that in solution, which suggests the epic movie of the PYP photocycle is indeed based in reality.
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Affiliation(s)
- Friedrich Schotte
- National Institutes of Health, NIDDK, LCP, Bethesda, Maryland 20892, USA
| | - Hyun Sun Cho
- National Institutes of Health, NIDDK, LCP, Bethesda, Maryland 20892, USA
| | - Fred Dyda
- National Institutes of Health, NIDDK, LMB, Bethesda, Maryland 20892, USA
| | - Philip Anfinrud
- National Institutes of Health, NIDDK, LCP, Bethesda, Maryland 20892, USA
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2
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Kosheleva I, Henning R, Kim I, Kim SO, Kusel M, Srajer V. Sample-minimizing co-flow cell for time-resolved pump-probe X-ray solution scattering. JOURNAL OF SYNCHROTRON RADIATION 2023; 30:490-499. [PMID: 36891863 PMCID: PMC10000795 DOI: 10.1107/s1600577522012127] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 12/22/2022] [Indexed: 06/10/2023]
Abstract
A fundamental problem in biological sciences is understanding how macromolecular machines work and how the structural changes of a molecule are connected to its function. Time-resolved techniques are vital in this regard and essential for understanding the structural dynamics of biomolecules. Time-resolved small- and wide-angle X-ray solution scattering has the capability to provide a multitude of information about the kinetics and global structural changes of molecules under their physiological conditions. However, standard protocols for such time-resolved measurements often require significant amounts of sample, which frequently render time-resolved measurements impossible. A cytometry-type sheath co-flow cell, developed at the BioCARS 14-ID beamline at the Advanced Photon Source, USA, allows time-resolved pump-probe X-ray solution scattering measurements to be conducted with sample consumption reduced by more than ten times compared with standard sample cells and protocols. The comparative capabilities of the standard and co-flow experimental setups were demonstrated by studying time-resolved signals in photoactive yellow protein.
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Affiliation(s)
- Irina Kosheleva
- BioCARS, Center for Advanced Radiation Sources, The University of Chicago, 9700 South Cass Ave, Bld 434B, Lemont, IL 60439, USA
| | - Robert Henning
- BioCARS, Center for Advanced Radiation Sources, The University of Chicago, 9700 South Cass Ave, Bld 434B, Lemont, IL 60439, USA
| | - Insik Kim
- BioCARS, Center for Advanced Radiation Sources, The University of Chicago, 9700 South Cass Ave, Bld 434B, Lemont, IL 60439, USA
| | - Seong Ok Kim
- Department of Chemistry, Korea Advanced Institute of Science and Technology, E6-6 #513, 291 Daehak-ro, Daejeon, Yuseong-gu 34141, Republic of Korea
| | - Michael Kusel
- Kusel Design, 12 Coghlan Street, Niddrie, Wurundjeri Country 3042, Australia
| | - Vukica Srajer
- BioCARS, Center for Advanced Radiation Sources, The University of Chicago, 9700 South Cass Ave, Bld 434B, Lemont, IL 60439, USA
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3
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van Wilderen LJGW, Blankenburg L, Bredenbeck J. Femtosecond-to-millisecond mid-IR spectroscopy of Photoactive Yellow Protein uncovers structural micro-transitions of the chromophore's protonation mechanism. J Chem Phys 2022; 156:205103. [DOI: 10.1063/5.0091918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Protein structural dynamics can span many orders of magnitude in time. Photoactive Yellow Protein's (PYP) reversible photocycle encompasses picosecond isomerization of the light-absorbing chromophore as well as large scale protein backbone motions occurring on a millisecond timescale. Femtosecond-to-millisecond time-resolved mid-Infrared (IR) spectroscopy is employed here to uncover structural details of photocycle intermediates up to chromophore protonation and the first structural changes leading to formation of the partially-unfolded signalling state pB. The data show that a commonly thought stable transient photocycle intermediate is actually formed after a sequence of several smaller structural changes. We provide residue-specific spectroscopic evidence that protonation of the chromophore on a hundreds of microseconds timescale is delayed with respect to deprotonation of the nearby E46 residue. That implies that the direct proton donor is not E46 but most likely a water molecule. Such details may assist ongoing photocycle and protein folding simulation efforts on the complex and wide time-spanning photocycle of the model system PYP.
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4
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Absorption wavelength along chromophore low-barrier hydrogen bonds. iScience 2022; 25:104247. [PMID: 35521532 PMCID: PMC9062252 DOI: 10.1016/j.isci.2022.104247] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 03/18/2022] [Accepted: 04/07/2022] [Indexed: 11/22/2022] Open
Abstract
In low-barrier hydrogen bonds (H-bonds), the pKa values for the H-bond donor and acceptor moieties are nearly equal, whereas the redox potential values depend on the H+ position. Spectroscopic details of low-barrier H-bonds remain unclear. Here, we report the absorption wavelength along low-barrier H-bonds in protein environments, using a quantum mechanical/molecular mechanical approach. Low-barrier H-bonds form between Glu46 and p-coumaric acid (pCA) in the intermediate pRCW state of photoactive yellow protein and between Asp116 and the retinal Schiff base in the intermediate M-state of the sodium-pumping rhodopsin KR2. The H+ displacement of only ∼0.4 Å, which does not easily occur without low-barrier H-bonds, is responsible for the ∼50 nm-shift in the absorption wavelength. This may be a basis of how photoreceptor proteins have evolved to proceed photocycles using abundant protons. The low-barrier H-bond formation is a prerequisite for proton transfer How the absorption wavelength changes as H+ moves is an open question The H+ displacement of ∼0.4 Å leads to the absorption wavelength shift of ∼50 nm The localization of the molecular orbitals plays a key role in the wavelength shift
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5
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Mix LT, Hara M, Fuzell J, Kumauchi M, Kaledhonkar S, Xie A, Hoff WD, Larsen DS. Not All Photoactive Yellow Proteins Are Built Alike: Surprises and Insights into Chromophore Photoisomerization, Protonation, and Thermal Reisomerization of the Photoactive Yellow Protein Isolated from Salinibacter ruber. J Am Chem Soc 2021; 143:19614-19628. [PMID: 34780163 DOI: 10.1021/jacs.1c08910] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
We demonstrate that the Halorhodospira halophila (Hhal) photoactive yellow protein (PYP) is not representative of the greater PYP family. The photodynamics of the PYP isolated from Salinibacter ruber (Srub) is characterized with a comprehensive range of spectroscopic techniques including ultrafast transient absorption, photostationary light titrations, Fourier transform infrared, and cryokinetics spectroscopies. We demonstrate that the dark-adapted pG state consists of two subpopulations differing in the protonation state of the chromophore and that both are photoactive, with the protonated species undergoing excited-state proton transfer. However, the primary I0 photoproduct observed in the Hhal PYP photocycle is absent in the Srub PYP photodynamics, which indicates that this intermediate, while important in Hhal photodynamics, is not a critical intermediate in initiating all PYP photocycles. The excited-state lifetime of Srub PYP is the longest of any PYP resolved to date (∼30 ps), which we ascribe to the more constrained chromophore binding pocket of Srub PYP and the absence of the critical Arg52 residue found in Hhal PYP. The final stage of the Srub PYP photocycle involves the slowest known thermal dark reversion of a PYP (∼40 min vs 350 ms in Hhal PYP). This property allowed the characterization of a pH-dependent equilibrium between the light-adapted pB state with a protonated cis chromophore and a newly resolved pG' intermediate with a deprotonated cis chromophore and pG-like protein conformation. This result demonstates that protein conformational changes and chromophore deprotonation precede chromophore reisomerization during the thermal recovery of the PYP photocycle.
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Affiliation(s)
- L Tyler Mix
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Miwa Hara
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Jack Fuzell
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Masato Kumauchi
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Sandip Kaledhonkar
- Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Aihua Xie
- Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078, United States.,Center for Advanced Infrared Biology College of Arts and Sciences, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Wouter D Hoff
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, United States.,Center for Advanced Infrared Biology College of Arts and Sciences, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Delmar S Larsen
- Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
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6
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Konold PE, Arik E, Weißenborn J, Arents JC, Hellingwerf KJ, van Stokkum IHM, Kennis JTM, Groot ML. Confinement in crystal lattice alters entire photocycle pathway of the Photoactive Yellow Protein. Nat Commun 2020; 11:4248. [PMID: 32843623 PMCID: PMC7447820 DOI: 10.1038/s41467-020-18065-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 07/31/2020] [Indexed: 11/27/2022] Open
Abstract
Femtosecond time-resolved crystallography (TRC) on proteins enables resolving the spatial structure of short-lived photocycle intermediates. An open question is whether confinement and lower hydration of the proteins in the crystalline state affect the light-induced structural transformations. Here, we measured the full photocycle dynamics of a signal transduction protein often used as model system in TRC, Photoactive Yellow Protein (PYP), in the crystalline state and compared those to the dynamics in solution, utilizing electronic and vibrational transient absorption measurements from 100 fs over 12 decades in time. We find that the photocycle kinetics and structural dynamics of PYP in the crystalline form deviate from those in solution from the very first steps following photon absorption. This illustrates that ultrafast TRC results cannot be uncritically extrapolated to in vivo function, and that comparative spectroscopic experiments on proteins in crystalline and solution states can help identify structural intermediates under native conditions. Protein structural dynamics can be studied by time-resolved crystallography (TRC) and ultrafast transient spectroscopic methods. Here, the authors perform electronic and vibrational transient absorption measurements to characterise the full photocycle of Photoactive Yellow Protein (PYP) both in the crystalline and solution state and find that the photocycle kinetics and structural intermediates of PYP deviate in the crystalline state, which must be taken into consideration when planning TRC experiments.
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Affiliation(s)
- Patrick E Konold
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands
| | - Enis Arik
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands
| | - Jörn Weißenborn
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands
| | - Jos C Arents
- Laboratory for Microbiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park, 1098, XH, Amsterdam, The Netherlands
| | - Klaas J Hellingwerf
- Laboratory for Microbiology, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park, 1098, XH, Amsterdam, The Netherlands
| | - Ivo H M van Stokkum
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands
| | - John T M Kennis
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands
| | - Marie Louise Groot
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands.
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7
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Anstöter CS, Curchod BFE, Verlet JRR. Geometric and electronic structure probed along the isomerisation coordinate of a photoactive yellow protein chromophore. Nat Commun 2020; 11:2827. [PMID: 32499507 PMCID: PMC7272410 DOI: 10.1038/s41467-020-16667-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 05/15/2020] [Indexed: 01/29/2023] Open
Abstract
Understanding the connection between the motion of the nuclei in a molecule and the rearrangement of its electrons lies at the heart of chemistry. While many experimental methods have been developed to probe either the electronic or the nuclear structure on the timescale of atomic motion, very few have been able to capture both these changes in concert. Here, we use time-resolved photoelectron imaging to probe the isomerisation coordinate on the excited state of an isolated model chromophore anion of the photoactive yellow protein. By probing both the electronic structure changes as well as nuclear dynamics, we are able to uniquely measure isomerisation about a specific bond. Our results demonstrate that the photoelectron signal dispersed in time, energy and angle combined with calculations can track the evolution of both electronic and geometric structure along the adiabatic state, which in turn defines that chemical transformation. Resolving concerted nuclear and electronic motion in real-time is a primary goal in chemistry. The authors monitor nuclear and valence electronic dynamics in the excited state single-bond isomerisation of a chromophore of photoactive yellow protein, using time-resolved photoelectron imaging and electronic structure calculations.
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Affiliation(s)
- Cate S Anstöter
- Department of Chemistry, Durham University, Durham, DH1 3LE, UK
| | | | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham, DH1 3LE, UK.
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8
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Illumination guidelines for ultrafast pump-probe experiments by serial femtosecond crystallography. Nat Methods 2020; 17:681-684. [PMID: 32451477 DOI: 10.1038/s41592-020-0847-3] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 04/17/2020] [Indexed: 12/20/2022]
Abstract
Time-resolved crystallography with X-ray free-electron lasers enables structural characterization of light-induced reactions on ultrafast timescales. To be biologically and chemically relevant, such studies must be carried out in an appropriate photoexcitation regime to avoid multiphoton artifacts, a common issue in recent studies. We describe numerical and experimental approaches to determine how many photons are needed for single-photon excitation in microcrystals, taking into account losses by scattering.
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9
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Wilson KS, Mapile AN, Wong CY. Broadband single-shot transient absorption spectroscopy. OPTICS EXPRESS 2020; 28:11339-11355. [PMID: 32403647 DOI: 10.1364/oe.390938] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 03/16/2020] [Indexed: 06/11/2023]
Abstract
The duration of transient absorption spectroscopy measurements typically limits the types of systems for which the excited state dynamics can be measured. We present a single-shot transient absorption (SSTA) instrument with a spatially encoded 60 ps time delay range and a 100 nm spectral range that is capable of acquiring a transient spectrum in 20 s. We describe methods to spatially overlap the flat-top pump and probe beams at the sample plane, calibrate the spatially encoded time delay, and correct for non-uniform excitation density. SSTA measurements of organic materials in solution and film demonstrate this technique.
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10
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Imamoto Y, Sasayama H, Harigai M, Furutani Y, Kataoka M. Regulation of Photocycle Kinetics of Photoactive Yellow Protein by Modulating Flexibility of the β-Turn. J Phys Chem B 2020; 124:1452-1459. [PMID: 32017565 DOI: 10.1021/acs.jpcb.9b11879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The role of the significant flexibility of the β-turn in photoactive yellow protein (PYP) due to Gly115 was studied. G115A and G115P mutations were observed to accelerate the photocycle and shift the equilibrium between the late photocycle intermediate (pB) and its precursor (pR) toward pR. Thermodynamic analysis of dark-state recovery from pB demonstrated that the transition state (pB⧧) has a negative change in transition heat capacity, suggesting that an exposed hydrophobic surface of pB is buried in pB⧧. Fourier transform infrared spectroscopy showed that the structural ensemble of pB is populated by the compact structure in G115P. Taken together, the rigid structure induced by mutation of Gly115 facilitates its transition to pB⧧, which adopts a substantially more compact structure as opposed to the ensemble-averaged structure of pB. The photocycle kinetics of PYP may be fine-tuned by modulating the flexibility of the 115 loop to activate an appropriate number of transducer proteins.
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Affiliation(s)
- Yasushi Imamoto
- Department of Biophysics, Graduate School of Science , Kyoto University , Kyoto 606-8502 , Japan
| | - Hiroaki Sasayama
- Graduate School of Materials Science , Nara Institute of Science and Technology , Ikoma , Nara 630-0192 , Japan
| | - Miki Harigai
- Graduate School of Materials Science , Nara Institute of Science and Technology , Ikoma , Nara 630-0192 , Japan
| | - Yuji Furutani
- Department of Life and Coordination-Complex Molecular Science, Institute for Molecular Science , National Institutes of Natural Sciences , 38 Nishigo-Naka, Myodaiji , Okazaki 444-8585 , Japan.,Department of Structural Molecular Science , The Graduate University for Advanced Studies (SOKENDAI) , 38 Nishigo-Naka, Myodaiji , Okazaki 444-8585 , Japan
| | - Mikio Kataoka
- Graduate School of Materials Science , Nara Institute of Science and Technology , Ikoma , Nara 630-0192 , Japan
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11
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Blankenburg L, Schroeder L, Habenstein F, Błasiak B, Kottke T, Bredenbeck J. Following local light-induced structure changes and dynamics of the photoreceptor PYP with the thiocyanate IR label. Phys Chem Chem Phys 2019; 21:6622-6634. [PMID: 30855039 DOI: 10.1039/c8cp05399e] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photoactive Yellow Protein (PYP) is a bacterial blue light receptor that enters a photocycle after excitation. The intermediate states are formed on time scales ranging from femtoseconds up to hundreds of milliseconds, after which the signaling state with a lifetime of about 1 s is reached. To investigate structural changes and dynamics, we incorporated the SCN IR label at distinct positions of the photoreceptor via cysteine mutation and cyanylation. FT-IR measurements of the SCN label at different sites of the well-established dark state structure of PYP characterized the spectral response of the label to differences in the environment. Under constant blue light irradiation, we observed the formation of the signaling state with significant changes of wavenumber and lineshape of the SCN bands. Thereby we deduced light-induced structural changes in the local environment of the labels. These results were supported by molecular dynamics simulations on PYP providing the solvent accessible surface area (SASA) at the different positions. To follow protein dynamics via the SCN label during the photocycle, we performed step-scan FT-IR measurements with a time resolution of 10 μs. Global analysis yielded similar time constants of τ1 = 70 μs, τ2 = 640 μs, and τ3 > 20 ms for the wild type and τ1 = 36 μs, τ2 = 530 μs, and τ3 > 20 ms for the SCN-labeled mutant PYP-A44C*, a mutant which provided a sufficiently large SCN difference signal to measure step-scan FT-IR spectra. In comparison to the protein (amide, E46) and chromophore bands the dynamics of the SCN label show a different behavior. This result indicates that the local kinetics sensed by the label are different from the global protein kinetics.
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Affiliation(s)
- Larissa Blankenburg
- Johann Wolfgang Goethe-University, Institute of Biophysics, Max-von-Laue-Str. 1, 60438 Frankfurt am Main, Germany.
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12
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Krekic S, Nagy D, Taneva SG, Fábián L, Zimányi L, Dér A. Spectrokinetic characterization of photoactive yellow protein films for integrated optical applications. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2019; 48:465-473. [PMID: 30905045 PMCID: PMC6647221 DOI: 10.1007/s00249-019-01353-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 02/19/2019] [Accepted: 03/04/2019] [Indexed: 11/02/2022]
Abstract
In this paper, the photocycle of the dried photoactive yellow protein film has been investigated in different humidity environments, in order to characterize its nonlinear optical properties for possible integrated optical applications. The light-induced spectral changes of the protein films were monitored by an optical multichannel analyser set-up, while the accompanying refractive index changes were measured with the optical waveguide lightmode spectroscopy method. To determine the number and kinetics of spectral intermediates in the photocycle, the absorption kinetic data were analysed by singular value decomposition and multiexponential fitting methods, whose results were used in a subsequent step of fitting a photocycle model to the data. The absorption signals of the films were found to be in strong correlation with the measured light-induced refractive index changes, whose size and kinetics imply that photoactive yellow protein may be a good alternative for utilization as an active nonlinear optical material in future integrated optical applications.
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Affiliation(s)
- Szilvia Krekic
- Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, P.O. Box 521, Szeged, 6701, Hungary.
| | - Dávid Nagy
- Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, P.O. Box 521, Szeged, 6701, Hungary
| | - Stefka G Taneva
- Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., bl. 21, Sofia, 1113, Bulgaria
| | - László Fábián
- Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, P.O. Box 521, Szeged, 6701, Hungary
| | - László Zimányi
- Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, P.O. Box 521, Szeged, 6701, Hungary
| | - András Dér
- Institute of Biophysics, Biological Research Centre, Hungarian Academy of Sciences, Temesvári krt. 62, P.O. Box 521, Szeged, 6701, Hungary
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13
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Mix LT, Carroll EC, Morozov D, Pan J, Gordon WR, Philip A, Fuzell J, Kumauchi M, van Stokkum I, Groenhof G, Hoff WD, Larsen DS. Excitation-Wavelength-Dependent Photocycle Initiation Dynamics Resolve Heterogeneity in the Photoactive Yellow Protein from Halorhodospira halophila. Biochemistry 2018; 57:1733-1747. [PMID: 29465990 DOI: 10.1021/acs.biochem.7b01114] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Photoactive yellow proteins (PYPs) make up a diverse class of blue-light-absorbing bacterial photoreceptors. Electronic excitation of the p-coumaric acid chromophore covalently bound within PYP results in triphasic quenching kinetics; however, the molecular basis of this behavior remains unresolved. Here we explore this question by examining the excitation-wavelength dependence of the photodynamics of the PYP from Halorhodospira halophila via a combined experimental and computational approach. The fluorescence quantum yield, steady-state fluorescence emission maximum, and cryotrapping spectra are demonstrated to depend on excitation wavelength. We also compare the femtosecond photodynamics in PYP at two excitation wavelengths (435 and 475 nm) with a dual-excitation-wavelength-interleaved pump-probe technique. Multicompartment global analysis of these data demonstrates that the excited-state photochemistry of PYP depends subtly, but convincingly, on excitation wavelength with similar kinetics with distinctly different spectral features, including a shifted ground-state beach and altered stimulated emission oscillator strengths and peak positions. Three models involving multiple excited states, vibrationally enhanced barrier crossing, and inhomogeneity are proposed to interpret the observed excitation-wavelength dependence of the data. Conformational heterogeneity was identified as the most probable model, which was supported with molecular mechanics simulations that identified two levels of inhomogeneity involving the orientation of the R52 residue and different hydrogen bonding networks with the p-coumaric acid chromophore. Quantum calculations were used to confirm that these inhomogeneities track to altered spectral properties consistent with the experimental results.
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Affiliation(s)
- L Tyler Mix
- Department of Chemistry , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States
| | - Elizabeth C Carroll
- Department of Chemistry , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States
| | - Dmitry Morozov
- Department of Chemistry and NanoScience Center , University of Jyväskylä , P.O. Box 35, 40014 Jyväskylä , Finland
| | - Jie Pan
- Department of Chemistry , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States
| | | | | | - Jack Fuzell
- Department of Chemistry , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States
| | - Masato Kumauchi
- Department of Microbiology and Molecular Genetics , Oklahoma State University , Stillwater , Oklahoma 74078 , United States
| | - Ivo van Stokkum
- Faculty of Sciences , Vrije Universiteit Amsterdam , De Boelelaan 1081 , 1081 HV Amsterdam , The Netherlands
| | - Gerrit Groenhof
- Department of Chemistry and NanoScience Center , University of Jyväskylä , P.O. Box 35, 40014 Jyväskylä , Finland
| | - Wouter D Hoff
- Department of Microbiology and Molecular Genetics , Oklahoma State University , Stillwater , Oklahoma 74078 , United States
| | - Delmar S Larsen
- Department of Chemistry , University of California, Davis , One Shields Avenue , Davis , California 95616 , United States
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14
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Mizutani Y. Time-Resolved Resonance Raman Spectroscopy and Application to Studies on Ultrafast Protein Dynamics. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2017. [DOI: 10.1246/bcsj.20170218] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yasuhisa Mizutani
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
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15
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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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16
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Schmidt M. A short history of structure based research on the photocycle of photoactive yellow protein. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2017; 4:032201. [PMID: 28191482 PMCID: PMC5291790 DOI: 10.1063/1.4974172] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 01/04/2017] [Indexed: 05/07/2023]
Abstract
The goals of time-resolved macromolecular crystallography are to extract the molecular structures of the reaction intermediates and the reaction dynamics from time-resolved X-ray data alone. To develop the techniques of time-resolved crystallography, biomolecules with special properties are required. The Photoactive Yellow Protein is the most sparkling of these.
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Affiliation(s)
- Marius Schmidt
- Physics Department, University of Wisconsin-Milwaukee , 3135 N. Maryland Ave, Milwaukee, Wisconsin 53211, USA
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17
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Mix LT, Kirpich J, Kumauchi M, Ren J, Vengris M, Hoff WD, Larsen DS. Bifurcation in the Ultrafast Dynamics of the Photoactive Yellow Proteins from Leptospira biflexa and Halorhodospira halophila. Biochemistry 2016; 55:6138-6149. [DOI: 10.1021/acs.biochem.6b00547] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- L. Tyler Mix
- Department
of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Julia Kirpich
- Department
of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
| | - Masato Kumauchi
- Department
of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Jie Ren
- Department
of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Mikas Vengris
- Faculty
of Physics, Laser Research Centre, Vilnius University, Sauletekio
10, LT-10233 Vilnius, Lithuania
| | - Wouter D. Hoff
- Department
of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Delmar S. Larsen
- Department
of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, United States
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18
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Cho HS, Schotte F, Dashdorj N, Kyndt J, Henning R, Anfinrud PA. Picosecond Photobiology: Watching a Signaling Protein Function in Real Time via Time-Resolved Small- and Wide-Angle X-ray Scattering. J Am Chem Soc 2016; 138:8815-23. [PMID: 27305463 DOI: 10.1021/jacs.6b03565] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The capacity to respond to environmental changes is crucial to an organism's survival. Halorhodospira halophila is a photosynthetic bacterium that swims away from blue light, presumably in an effort to evade photons energetic enough to be genetically harmful. The protein responsible for this response is believed to be photoactive yellow protein (PYP), whose chromophore photoisomerizes from trans to cis in the presence of blue light. We investigated the complete PYP photocycle by acquiring time-resolved small and wide-angle X-ray scattering patterns (SAXS/WAXS) over 10 decades of time spanning from 100 ps to 1 s. Using a sequential model, global analysis of the time-dependent scattering differences recovered four intermediates (pR0/pR1, pR2, pB0, pB1), the first three of which can be assigned to prior time-resolved crystal structures. The 1.8 ms pB0 to pB1 transition produces the PYP signaling state, whose radius of gyration (Rg = 16.6 Å) is significantly larger than that for the ground state (Rg = 14.7 Å) and is therefore inaccessible to time-resolved protein crystallography. The shape of the signaling state, reconstructed using GASBOR, is highly anisotropic and entails significant elongation of the long axis of the protein. This structural change is consistent with unfolding of the 25 residue N-terminal domain, which exposes the β-scaffold of this sensory protein to a potential binding partner. This mechanistically detailed description of the complete PYP photocycle, made possible by time-resolved crystal and solution studies, provides a framework for understanding signal transduction in proteins and for assessing and validating theoretical/computational approaches in protein biophysics.
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Affiliation(s)
- Hyun Sun Cho
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Friedrich Schotte
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - Naranbaatar Dashdorj
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
| | - John Kyndt
- College of Science and Technology, Bellevue University , Bellevue, Nebraska 68005, United States
| | - Robert Henning
- Center for Advanced Radiation Sources, University of Chicago , Chicago, Illinois 60637, United States
| | - Philip A Anfinrud
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
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19
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New AB2 type two-photon absorption dyes for well-separated dual-emission: molecular preorganization based approach to photophysical properties. Tetrahedron 2016. [DOI: 10.1016/j.tet.2016.04.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Gamiz-Hernandez AP, Kaila VRI. Conversion of light-energy into molecular strain in the photocycle of the photoactive yellow protein. Phys Chem Chem Phys 2016; 18:2802-9. [DOI: 10.1039/c5cp05244k] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The Photoactive Yellow Protein (PYP) converts light energy into molecular strain, stored in the early pR0-photocycle intermediate.
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Affiliation(s)
| | - Ville R. I. Kaila
- Department Chemie
- Technische Universität München (TUM)
- D-85747 Garching
- Germany
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21
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Hamada N, Tan Z, Kanematsu Y, Inazumi N, Nakamura R. Influence of a chromophore analogue in the protein cage of a photoactive yellow protein. Photochem Photobiol Sci 2015; 14:1722-8. [PMID: 26178816 DOI: 10.1039/c5pp00176e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Time-resolved spectra of a photoactive yellow protein (PYP) containing cyano-p-coumaric acid (CHCA) were recorded. To understand the mechanism of photo-isomerization, an electron-withdrawing CN group was introduced into the PYP to alter the C[double bond, length as m-dash]C double bond character. Free CHCA chromophores in aqueous solution underwent photo-isomerization whereas PYP with a bound CHCA (PYP-CN) exhibited no photocycle at acidic or alkaline pH or in urea and other solutions. Furthermore, no photocycle was observed with PYP mutants after illumination. This phenomenon cannot be fully explained by the electron-withdrawing properties of the CN group. We conclude that the CHCA chromophore in PYP was locked in the protein cage and that the CN group interacted with the protein residues.
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Affiliation(s)
- Norio Hamada
- Science & Technology Entrepreneurship Laboratory (e-square), Osaka University, 2-1 Yamadaoka, Suita, Osaka, Japan.
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22
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Tenboer J, Basu S, Zatsepin N, Pande K, Milathianaki D, Frank M, Hunter M, Boutet S, Williams GJ, Koglin JE, Oberthuer D, Heymann M, Kupitz C, Conrad C, Coe J, Roy-Chowdhury S, Weierstall U, James D, Wang D, Grant T, Barty A, Yefanov O, Scales J, Gati C, Seuring C, Srajer V, Henning R, Schwander P, Fromme R, Ourmazd A, Moffat K, Van Thor JJ, Spence JCH, Fromme P, Chapman HN, Schmidt M. Time-resolved serial crystallography captures high-resolution intermediates of photoactive yellow protein. Science 2014; 346:1242-6. [PMID: 25477465 DOI: 10.1126/science.1259357] [Citation(s) in RCA: 336] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Serial femtosecond crystallography using ultrashort pulses from x-ray free electron lasers (XFELs) enables studies of the light-triggered dynamics of biomolecules. We used microcrystals of photoactive yellow protein (a bacterial blue light photoreceptor) as a model system and obtained high-resolution, time-resolved difference electron density maps of excellent quality with strong features; these allowed the determination of structures of reaction intermediates to a resolution of 1.6 angstroms. Our results open the way to the study of reversible and nonreversible biological reactions on time scales as short as femtoseconds under conditions that maximize the extent of reaction initiation throughout the crystal.
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Affiliation(s)
- Jason Tenboer
- Physics Department, University of Wisconsin, Milwaukee, WI 53211, USA
| | - Shibom Basu
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA
| | - Nadia Zatsepin
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Kanupriya Pande
- Physics Department, University of Wisconsin, Milwaukee, WI 53211, USA
| | - Despina Milathianaki
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Matthias Frank
- Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Mark Hunter
- Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Sébastien Boutet
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Garth J Williams
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Jason E Koglin
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Dominik Oberthuer
- Centre for Ultrafast Imaging, University of Hamburg, 22761 Hamburg, Germany
| | - Michael Heymann
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Christopher Kupitz
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA
| | - Chelsie Conrad
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA
| | - Jesse Coe
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA
| | - Shatabdi Roy-Chowdhury
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA
| | - Uwe Weierstall
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Daniel James
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Dingjie Wang
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Thomas Grant
- Hauptman-Woodward Institute, State University of New York at Buffalo, 700 Ellicott Street, Buffalo, NY 14203, USA
| | - Anton Barty
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Oleksandr Yefanov
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Jennifer Scales
- Physics Department, University of Wisconsin, Milwaukee, WI 53211, USA
| | - Cornelius Gati
- Centre for Ultrafast Imaging, University of Hamburg, 22761 Hamburg, Germany.,Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Carolin Seuring
- Centre for Ultrafast Imaging, University of Hamburg, 22761 Hamburg, Germany
| | - Vukica Srajer
- Center for Advanced Radiation Sources, University of Chicago, Chicago, IL 60637, USA
| | - Robert Henning
- Center for Advanced Radiation Sources, University of Chicago, Chicago, IL 60637, USA
| | - Peter Schwander
- Physics Department, University of Wisconsin, Milwaukee, WI 53211, USA
| | - Raimund Fromme
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA
| | - Abbas Ourmazd
- Physics Department, University of Wisconsin, Milwaukee, WI 53211, USA
| | - Keith Moffat
- Center for Advanced Radiation Sources, University of Chicago, Chicago, IL 60637, USA.,Department of Biochemistry and Molecular Biology and Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637, USA
| | - Jasper J Van Thor
- Faculty of Natural Sciences, Life Sciences, Imperial College, London SW7 2AZ, UK
| | - John C H Spence
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Petra Fromme
- Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA
| | - Henry N Chapman
- Centre for Ultrafast Imaging, University of Hamburg, 22761 Hamburg, Germany.,Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Marius Schmidt
- Physics Department, University of Wisconsin, Milwaukee, WI 53211, USA.,Physics Department, University of Wisconsin, Milwaukee, WI 53211, USA.
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23
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Zhu J, Vreede J, Hospes M, Arents J, Kennis JTM, van Stokkum IHM, Hellingwerf KJ, Groot ML. Short Hydrogen Bonds and Negative Charge in Photoactive Yellow Protein Promote Fast Isomerization but not High Quantum Yield. J Phys Chem B 2014; 119:2372-83. [DOI: 10.1021/jp506785q] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Jingyi Zhu
- Department
of Physics and Astronomy, Faculty of Sciences, LaserLab, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | | | | | | | - John T. M. Kennis
- Department
of Physics and Astronomy, Faculty of Sciences, LaserLab, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Ivo H. M. van Stokkum
- Department
of Physics and Astronomy, Faculty of Sciences, LaserLab, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | | | - Marie Louise Groot
- Department
of Physics and Astronomy, Faculty of Sciences, LaserLab, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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24
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Schmidt M, Saldin DK. Enzyme transient state kinetics in crystal and solution from the perspective of a time-resolved crystallographer. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2014; 1:024701. [PMID: 26798774 PMCID: PMC4711602 DOI: 10.1063/1.4869472] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 03/13/2014] [Indexed: 05/29/2023]
Abstract
With recent technological advances at synchrotrons [Graber et al., J. Synchrotron Radiat. 18, 658-670 (2011)], it is feasible to rapidly collect time-resolved crystallographic data at multiple temperature settings [Schmidt et al., Acta Crystallogr. D 69, 2534-2542 (2013)], from which barriers of activation can be extracted. With the advent of fourth generation X-ray sources, new opportunities emerge to investigate structure and dynamics of biological macromolecules in real time [M. Schmidt, Adv. Condens. Matter Phys. 2013, 1-10] in crystals and potentially from single molecules in random orientation in solution [Poon et al., Adv. Condens. Matter Phys. 2013, 750371]. Kinetic data from time-resolved experiments on short time-scales must be interpreted in terms of chemical kinetics [Steinfeld et al., Chemical Kinetics and Dynamics, 2nd ed. (Prentience Hall, 1985)] and tied to existing time-resolved experiments on longer time-scales [Schmidt et al., Acta Crystallogr. D 69, 2534-2542 (2013); Jung et al., Nat. Chem. 5, 212-220 (2013)]. With this article, we will review and outline steps that are required to routinely determine the energetics of reactions in biomolecules in crystal and solution with newest X-ray sources. In eight sections, we aim to describe concepts and experimental details that may help to inspire new approaches to collect and interpret these data.
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Affiliation(s)
- Marius Schmidt
- Physics Department, University of Wisconsin , Milwaukee, Wisconsin 53211, USA
| | - Dilano K Saldin
- Physics Department, University of Wisconsin , Milwaukee, Wisconsin 53211, USA
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25
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Creelman M, Kumauchi M, Hoff WD, Mathies RA. Chromophore Dynamics in the PYP Photocycle from Femtosecond Stimulated Raman Spectroscopy. J Phys Chem B 2014; 118:659-67. [DOI: 10.1021/jp408584v] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Mark Creelman
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - Masato Kumauchi
- Department
of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Wouter D. Hoff
- Department
of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma 74078, United States
| | - Richard A. Mathies
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
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26
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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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27
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Ishikita H, Saito K. Proton transfer reactions and hydrogen-bond networks in protein environments. J R Soc Interface 2013; 11:20130518. [PMID: 24284891 DOI: 10.1098/rsif.2013.0518] [Citation(s) in RCA: 141] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In protein environments, proton transfer reactions occur along polar or charged residues and isolated water molecules. These species consist of H-bond networks that serve as proton transfer pathways; therefore, thorough understanding of H-bond energetics is essential when investigating proton transfer reactions in protein environments. When the pKa values (or proton affinity) of the H-bond donor and acceptor moieties are equal, significantly short, symmetric H-bonds can be formed between the two, and proton transfer reactions can occur in an efficient manner. However, such short, symmetric H-bonds are not necessarily stable when they are situated near the protein bulk surface, because the condition of matching pKa values is opposite to that required for the formation of strong salt bridges, which play a key role in protein-protein interactions. To satisfy the pKa matching condition and allow for proton transfer reactions, proteins often adjust the pKa via electron transfer reactions or H-bond pattern changes. In particular, when a symmetric H-bond is formed near the protein bulk surface as a result of one of these phenomena, its instability often results in breakage, leading to large changes in protein conformation.
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Affiliation(s)
- Hiroshi Ishikita
- Department of Biological Sciences, Graduate School of Science, Osaka University, , Machikaneyama-cho 1-1, Toyonaka 560-0043, Japan
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28
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Cho HS, Schotte F, Dashdorj N, Kyndt J, Anfinrud PA. Probing anisotropic structure changes in proteins with picosecond time-resolved small-angle X-ray scattering. J Phys Chem B 2013; 117:15825-32. [PMID: 24125473 DOI: 10.1021/jp407593j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We have exploited the principle of photoselection and the method of time-resolved small-angle X-ray scattering (SAXS) to investigate protein size and shape changes following photoactivation of photoactive yellow protein (PYP) in solution with ∼150 ps time resolution. This study partially overcomes the orientational average intrinsic to solution scattering methods and provides structural information at a higher level of detail. Photoactivation of the p-coumaric acid (pCA) chromophore in PYP produces a highly contorted, short-lived, red-shifted intermediate (pR0), and triggers prompt, protein compaction of approximately 0.3% along the direction defined by the electronic transition dipole moment of the chromophore. Contraction along this dimension is accompanied by expansion along the orthogonal directions, with the net protein volume change being approximately -0.25%. More than half the strain arising from formation of pR0 is relieved by the pR0 to pR1 structure transition (1.8 ± 0.2 ns), with the persistent strain presumably contributing to the driving force needed to generate the spectroscopically blue-shifted pB signaling state. The results reported here are consistent with the near-atomic resolution structural dynamics reported in a recent time-resolved Laue crystallography study of PYP crystals and suggest that the early time structural dynamics in the crystalline state carry over to proteins in solution.
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Affiliation(s)
- Hyun Sun Cho
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892, United States
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29
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Mendonça L, Hache F, Changenet-Barret P, Plaza P, Chosrowjan H, Taniguchi S, Imamoto Y. Ultrafast Carbonyl Motion of the Photoactive Yellow Protein Chromophore Probed by Femtosecond Circular Dichroism. J Am Chem Soc 2013; 135:14637-43. [DOI: 10.1021/ja404503q] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Lucille Mendonça
- Laboratoire d’Optique et Biosciences, Ecole Polytechnique/CNRS/INSERM, 91128 Palaiseau cedex, France
| | - François Hache
- Laboratoire d’Optique et Biosciences, Ecole Polytechnique/CNRS/INSERM, 91128 Palaiseau cedex, France
| | | | - Pascal Plaza
- Ecole Normale Supérieure,
Département de Chimie, UMR 8640 CNRS-ENS-UPMC, 24 rue Lhomond,
75005 Paris, France
| | - Haik Chosrowjan
- Institute for Laser Technology, 2-6 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Seiji Taniguchi
- Institute for Laser Technology, 2-6 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yasushi Imamoto
- Department
of Biophysics, Graduate School of Sciences, Kyoto University, Kyoto 6068502, Japan
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30
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Purwar N, Tenboer J, Tripathi S, Schmidt M. Spectroscopic studies of model photo-receptors: validation of a nanosecond time-resolved micro-spectrophotometer design using photoactive yellow protein and α-phycoerythrocyanin. Int J Mol Sci 2013; 14:18881-98. [PMID: 24065094 PMCID: PMC3794812 DOI: 10.3390/ijms140918881] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 08/27/2013] [Accepted: 09/02/2013] [Indexed: 12/01/2022] Open
Abstract
Time-resolved spectroscopic experiments have been performed with protein in solution and in crystalline form using a newly designed microspectrophotometer. The time-resolution of these experiments can be as good as two nanoseconds (ns), which is the minimal response time of the image intensifier used. With the current setup, the effective time-resolution is about seven ns, determined mainly by the pulse duration of the nanosecond laser. The amount of protein required is small, on the order of 100 nanograms. Bleaching, which is an undesirable effect common to photoreceptor proteins, is minimized by using a millisecond shutter to avoid extensive exposure to the probing light. We investigate two model photoreceptors, photoactive yellow protein (PYP), and α-phycoerythrocyanin (α-PEC), on different time scales and at different temperatures. Relaxation times obtained from kinetic time-series of difference absorption spectra collected from PYP are consistent with previous results. The comparison with these results validates the capability of this spectrophotometer to deliver high quality time-resolved absorption spectra.
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Affiliation(s)
- Namrta Purwar
- Department of Physics, University of Wisconsin-Milwaukee, 1900 E. Kenwood Blvd., Milwaukee, WI 53211, USA.
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31
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Thellamurege NM, Cui F, Li H. Quantum mechanical/molecular mechanical/continuum style solvation model: Time-dependent density functional theory. J Chem Phys 2013; 139:084106. [DOI: 10.1063/1.4819139] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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32
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Liu J, Yabushita A, Taniguchi S, Chosrowjan H, Imamoto Y, Sueda K, Miyanaga N, Kobayashi T. Ultrafast Time-Resolved Pump–Probe Spectroscopy of PYP by a Sub-8 fs Pulse Laser at 400 nm. J Phys Chem B 2013; 117:4818-26. [DOI: 10.1021/jp4001016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jun Liu
- Advanced Ultrafast Laser Research
Center, University of Electro-Communications, Chofugaoka 1-5-1, Chofu, Tokyo 182-8585 Japan
- State Key Laboratory of High
Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
- Core Research for Evolutional
Science and Technology (CREST), Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Atsushi Yabushita
- Department of Electrophysics, National Chiao Tung University, 1001 Ta Hsueh Road,
Hsinchu 300, Taiwan
| | - Seiji Taniguchi
- Institute
for Laser Technology, Osaka University,
Yamadaoka 2-6, Suita Osaka, 565-0871
Japan
| | - Haik Chosrowjan
- Institute
for Laser Technology, Osaka University,
Yamadaoka 2-6, Suita Osaka, 565-0871
Japan
| | - Yasushi Imamoto
- Department of Biophysics,
Graduate
School of Science, Kyoto University, Kitashirakawa-Oiwake,
Sakyo, Kyoto 606-8502 Japan
| | - Keiichi Sueda
- Institute of Laser Engineering, Osaka University, Yamadakami 2-6, Suita 565-0871, Ibaraki
567-0047, Japan
| | - Noriaki Miyanaga
- Institute of Laser Engineering, Osaka University, Yamadakami 2-6, Suita 565-0871, Ibaraki
567-0047, Japan
| | - Takayoshi Kobayashi
- Advanced Ultrafast Laser Research
Center, University of Electro-Communications, Chofugaoka 1-5-1, Chofu, Tokyo 182-8585 Japan
- Core Research for Evolutional
Science and Technology (CREST), Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
- Department of Electrophysics, National Chiao Tung University, 1001 Ta Hsueh Road,
Hsinchu 300, Taiwan
- Institute of Laser Engineering, Osaka University, Yamadakami 2-6, Suita 565-0871, Ibaraki
567-0047, Japan
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33
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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: 146] [Impact Index Per Article: 13.3] [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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34
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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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35
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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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36
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Saito K, Ishikita H. Formation of an unusually short hydrogen bond in photoactive yellow protein. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012. [PMID: 23201477 DOI: 10.1016/j.bbabio.2012.11.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The photoactive chromophore of photoactive yellow protein (PYP) is p-coumaric acid (pCA). In the ground state, the pCA chromophore exists as a phenolate anion, which is H-bonded by protonated Glu46 (O(Glu46)-O(pCA)=~2.6Å) and protonated Tyr42. On the other hand, the O(Glu46)-O(pCA) H-bond was unusually short (O(Glu46)-O(pCA)=2.47Å) in the intermediate pR(CW) state observed in time-resolved Laue diffraction studies. To understand how the existence of the unusually short H-bond is energetically possible, we analyzed the H-bond energetics adopting a quantum mechanical/molecular mechanical (QM/MM) approach based on the atomic coordinates of the PYP crystal structures. In QM/MM calculations, the O(Glu46)-O(pCA) bond is 2.60Å in the ground state, where Tyr42 donates an H-bond to pCA. In contrast, when the hydroxyl group of Tyr42 is flipped away from pCA, the H-bond was significantly shortened to 2.49Å in the ground state. The same H-bond pattern reproduced the unusually short H-bond in the pR(CW) structure (O(Glu46)-O(pCA)=2.49Å). Intriguingly, the potential-energy profile resembles that of a single-well H-bond, suggesting that the pK(a) values of the donor (Glu46) and acceptor (pCA) moieties are nearly equal. The present results indicate that the "equal pK(a)" requirement for formation of single-well or low-barrier H-bond (LBHB) is satisfied only when Tyr42 does not donate an H-bond to pCA, and argue against the possibility that the O(Glu46)-O(pCA) bond is an LBHB in the ground state, where Tyr42 donates an H-bond to pCA.
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Affiliation(s)
- Keisuke Saito
- Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto, Japan
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37
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Watching a signaling protein function in real time via 100-ps time-resolved Laue crystallography. Proc Natl Acad Sci U S A 2012; 109:19256-61. [PMID: 23132943 DOI: 10.1073/pnas.1210938109] [Citation(s) in RCA: 137] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
To understand how signaling proteins function, it is crucial to know the time-ordered sequence of events that lead to the signaling state. We recently developed on the BioCARS 14-IDB beamline at the Advanced Photon Source the infrastructure required to characterize structural changes in protein crystals with near-atomic spatial resolution and 150-ps time resolution, and have used this capability to track the reversible photocycle of photoactive yellow protein (PYP) following trans-to-cis photoisomerization of its p-coumaric acid (pCA) chromophore over 10 decades of time. The first of four major intermediates characterized in this study is highly contorted, with the pCA carbonyl rotated nearly 90° out of the plane of the phenolate. A hydrogen bond between the pCA carbonyl and the Cys69 backbone constrains the chromophore in this unusual twisted conformation. Density functional theory calculations confirm that this structure is chemically plausible and corresponds to a strained cis intermediate. This unique structure is short-lived (∼600 ps), has not been observed in prior cryocrystallography experiments, and is the progenitor of intermediates characterized in previous nanosecond time-resolved Laue crystallography studies. The structural transitions unveiled during the PYP photocycle include trans/cis isomerization, the breaking and making of hydrogen bonds, formation/relaxation of strain, and gated water penetration into the interior of the protein. This mechanistically detailed, near-atomic resolution description of the complete PYP photocycle provides a framework for understanding signal transduction in proteins, and for assessing and validating theoretical/computational approaches in protein biophysics.
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38
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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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39
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pH dependence of the photoactive yellow protein photocycle investigated by time-resolved crystallography. Biophys J 2012; 102:325-32. [PMID: 22339869 DOI: 10.1016/j.bpj.2011.11.4021] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 11/21/2011] [Accepted: 11/29/2011] [Indexed: 11/21/2022] Open
Abstract
Visualizing the three-dimensional structures of a protein during its biological activity is key to understanding its mechanism. In general, protein structure and function are pH-dependent. Changing the pH provides new insights into the mechanisms that are involved in protein activity. Photoactive yellow protein (PYP) is a signaling protein that serves as an ideal model for time-dependent studies on light-activated proteins. Its photocycle is studied extensively under different pH conditions. However, the structures of the intermediates remain unknown until time-resolved crystallography is employed. With the newest beamline developments, a comprehensive time series of Laue data can now be collected from a single protein crystal. This allows us to vary the pH. Here we present the first structure, to our knowledge, of a short-lived protein-inhibitor complex formed in the pB state of the PYP photocycle at pH 4. A water molecule that is transiently stabilized in the chromophore active site prevents the relaxation of the chromophore back to the trans configuration. As a result, the dark-state recovery is slowed down dramatically. At pH 9, PYP stops cycling through the pB state altogether. The electrostatic environment in the chromophore-binding site is the likely reason for this altered kinetics at different pH values.
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40
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Changenet-Barret P, Lacombat F, Plaza P. Reaction-coordinate tracking in the excited-state deactivation of the photoactive yellow protein chromophore in solution. J Photochem Photobiol A Chem 2012. [DOI: 10.1016/j.jphotochem.2012.03.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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41
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Schmidt M, Šrajer V, Purwar N, Tripathi S. The kinetic dose limit in room-temperature time-resolved macromolecular crystallography. JOURNAL OF SYNCHROTRON RADIATION 2012; 19:264-73. [PMID: 22338689 PMCID: PMC3284346 DOI: 10.1107/s090904951105549x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Accepted: 12/23/2011] [Indexed: 05/16/2023]
Abstract
Protein X-ray structures are determined with ionizing radiation that damages the protein at high X-ray doses. As a result, diffraction patterns deteriorate with the increased absorbed dose. Several strategies such as sample freezing or scavenging of X-ray-generated free radicals are currently employed to minimize this damage. However, little is known about how the absorbed X-ray dose affects time-resolved Laue data collected at physiological temperatures where the protein is fully functional in the crystal, and how the kinetic analysis of such data depends on the absorbed dose. Here, direct evidence for the impact of radiation damage on the function of a protein is presented using time-resolved macromolecular crystallography. The effect of radiation damage on the kinetic analysis of time-resolved X-ray data is also explored.
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Affiliation(s)
- M Schmidt
- Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA.
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42
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Oktaviani NA, Pool TJ, Kamikubo H, Slager J, Scheek RM, Kataoka M, Mulder FAA. Comprehensive determination of protein tyrosine pKa values for photoactive yellow protein using indirect 13C NMR spectroscopy. Biophys J 2012; 102:579-86. [PMID: 22325281 DOI: 10.1016/j.bpj.2011.12.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 11/23/2011] [Accepted: 12/05/2011] [Indexed: 10/14/2022] Open
Abstract
Upon blue-light irradiation, the bacterium Halorhodospira halophila is able to modulate the activity of its flagellar motor and thereby evade potentially harmful UV radiation. The 14 kDa soluble cytosolic photoactive yellow protein (PYP) is believed to be the primary mediator of this photophobic response, and yields a UV/Vis absorption spectrum that closely matches the bacterium's motility spectrum. In the electronic ground state, the para-coumaric acid (pCA) chromophore of PYP is negatively charged and forms two short hydrogen bonds to the side chains of Glu-46 and Tyr-42. The resulting acid triad is central to the marked pH dependence of the optical-absorption relaxation kinetics of PYP. Here, we describe an NMR approach to sequence-specifically follow all tyrosine side-chain protonation states in PYP from pH 3.41 to 11.24. The indirect observation of the nonprotonated (13)C(γ) resonances in sensitive and well-resolved two-dimensional (13)C-(1)H spectra proved to be pivotal in this effort, as observation of other ring-system resonances was hampered by spectral congestion and line-broadening due to ring flips. We observe three classes of tyrosine residues in PYP that exhibit very different pK(a) values depending on whether the phenolic side chain is solvent-exposed, buried, or hydrogen-bonded. In particular, our data show that Tyr-42 remains fully protonated in the pH range of 3.41-11.24, and that pH-induced changes observed in the photocycle kinetics of PYP cannot be caused by changes in the charge state of Tyr-42. It is therefore very unlikely that the pCA chromophore undergoes changes in its electrostatic interactions in the electronic ground state.
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Affiliation(s)
- Nur Alia Oktaviani
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, The Netherlands
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43
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Kim TW, Lee JH, Choi J, Kim KH, van Wilderen LJ, Guerin L, Kim Y, Jung YO, Yang C, Kim J, Wulff M, van Thor JJ, Ihee H. Protein structural dynamics of photoactive yellow protein in solution revealed by pump-probe X-ray solution scattering. J Am Chem Soc 2012; 134:3145-53. [PMID: 22304441 DOI: 10.1021/ja210435n] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Photoreceptor proteins play crucial roles in receiving light stimuli that give rise to the responses required for biological function. However, structural characterization of conformational transition of the photoreceptors has been elusive in their native aqueous environment, even for a prototype photoreceptor, photoactive yellow protein (PYP). We employ pump-probe X-ray solution scattering to probe the structural changes that occur during the photocycle of PYP in a wide time range from 3.16 μs to 300 ms. By the analysis of both kinetics and structures of the intermediates, the structural progression of the protein in the solution phase is vividly visualized. We identify four structurally distinct intermediates and their associated five time constants and reconstructed the molecular shapes of the four intermediates from time-independent, species-associated difference scattering curves. The reconstructed structures of the intermediates show the large conformational changes such as the protrusion of N-terminus, which is restricted in the crystalline phase due to the crystal contact and thus could not be clearly observed by X-ray crystallography. The protrusion of the N-terminus and the protein volume gradually increase with the progress of the photocycle and becomes maximal in the final intermediate, which is proposed to be the signaling state. The data not only reveal that a common kinetic mechanism is applicable to both the crystalline and the solution phases, but also provide direct evidence for how the sample environment influences structural dynamics and the reaction rates of the PYP photocycle.
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Affiliation(s)
- Tae Wu Kim
- Center for Time-Resolved Diffraction, Department of Chemistry, Graduate School of Nanoscience & Technology (WCU), KAIST, Daejeon, 305-701, Republic of Korea
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44
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Park N, Park KD, Chung Y, Jeong MS. Scanning absorption nanoscopy with supercontinuum light sources based on photonic crystal fiber. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2011; 82:123102. [PMID: 22225194 DOI: 10.1063/1.3665206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We have experimentally demonstrated a scanning absorption nanoscopy system combining a near-field scanning optical microscope with an absorption spectroscope using supercontinuum radiation generated by coupling a mode-locked Ti:sapphire pulse laser to a nonlinear photonic crystal fiber as a light source. For the performance test of the system, the absorption spectrum and near-field absorption image of Rhodamine 6G were observed. As this system allows us to investigate the absorption properties and distribution of materials with high spatial resolution, it is expected to be effectively applied in various research areas.
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Affiliation(s)
- Noeul Park
- Graduate Program of Photonics and Applied Physics, Gwangju Institute of Science and Technology, Gwangju 500-712, South Korea
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45
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Sindhikara DJ, Yoshida N, Kataoka M, Hirata F. Solvent penetration in photoactive yellow protein R52Q mutant: A theoretical study. J Mol Liq 2011. [DOI: 10.1016/j.molliq.2011.04.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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46
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Mizuno M, Kamikubo H, Kataoka M, Mizutani Y. Changes in the hydrogen-bond network around the chromophore of photoactive yellow protein in the ground and excited states. J Phys Chem B 2011; 115:9306-10. [PMID: 21688774 DOI: 10.1021/jp2029399] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Changes in the hydrogen-bond (HB) network around the chromophore, p-coumaric acid (pCA), in the ground pG and excited pG* states were investigated for wild type (WT) photoactive yellow protein (PYP) and its mutants using ultraviolet resonance Raman (UVRR) spectroscopy. The intensity depletion of Tyr UVRR bands was observed upon photoexcitation of pCA to the pG* state. The spectral change was ascribed to strengthening of HB between pCA and Tyr42. Comparison of Raman intensities indicated that, in the pG state, the HB between pCA and Tyr42 in WT is a short HB, which is weaker than that in E46Q mutant. In the pG* state, the HB network around pCA of WT is similar to that of E46Q mutant. The present results demonstrate that the HB between pCA and Tyr42 and that between pCA and Glu46 are correlated with each other in the HB network.
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Affiliation(s)
- Misao Mizuno
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan
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47
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Rupenyan AB, Vreede J, van Stokkum IHM, Hospes M, Kennis JTM, Hellingwerf KJ, Groot ML. Proline 68 enhances photoisomerization yield in photoactive yellow protein. J Phys Chem B 2011; 115:6668-77. [PMID: 21542640 DOI: 10.1021/jp112113s] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In proteins and enzymes, the local environment of an active cofactor plays an important role in controlling the outcome of a functional reaction. In photoactive yellow protein (PYP), it ensures photoisomerization of the chromophore, a prerequisite for formation of a signaling state. PYP is the prototype of a PAS domain, and the preferred model system for the studies of molecular mechanisms of biological light sensing. We investigated the effect of replacing proline-68, positioned near but not in direct contact with the chromophore, with other neutral amino acids (alanine, glycine, and valine), using ultrafast spectroscopy probing the visible and the mid-IR spectral regions, and molecular simulation to understand the interactions tuning the efficiency of light signaling. Transient absorption measurements indicate that the quantum yield of isomerization in the mutants is lower than the yield observed for the wild type. Subpicosecond mid-IR spectra and molecular dynamics simulations of the four proteins reveal that the hydrogen bond interactions around the chromophore and the access of water molecules in the active site of the protein determine the efficiency of photoisomerization. The mutants provide additional hydrogen bonds to the chromophore, directly and by allowing more water molecules access to its binding pocket. We conclude that proline-68 in the wild type protein optimizes the yield of photochemistry by maintaining a weak hydrogen bond with the chromophore, at the same time restraining the entrance of water molecules close to the alkylic part of pCa. This study provides a molecular basis for the structural optimization of biological light sensing.
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Affiliation(s)
- Alisa B Rupenyan
- Department of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, Amsterdam, The Netherlands.
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48
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Changenet-Barret P, Loukou C, Ley C, Lacombat F, Plaza P, Mallet JM, Martin MM. Primary photodynamics of a biomimetic model of photoactive yellow protein (PYP). Phys Chem Chem Phys 2010; 12:13715-23. [DOI: 10.1039/c0cp00618a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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49
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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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50
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Hydrogen bond dynamics in the active site of photoactive yellow protein. Proc Natl Acad Sci U S A 2009; 106:9232-7. [PMID: 19470452 DOI: 10.1073/pnas.0900168106] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hydrogen bonds play major roles in biological structure and function. Nonetheless, hydrogen-bonded protons are not typically observed by X-ray crystallography, and most structural studies provide limited insight into the conformational plasticity of individual hydrogen bonds or the dynamical coupling present within hydrogen bond networks. We report the NMR detection of the hydrogen-bonded protons donated by Tyr-42 and Glu-46 to the chromophore oxygen in the active site of the bacterial photoreceptor, photoactive yellow protein (PYP). We have used the NMR resonances for these hydrogen bonds to probe their conformational properties and ability to rearrange in response to nearby electronic perturbation. The detection of geometric isotope effects transmitted between the Tyr-42 and Glu-46 hydrogen bonds provides strong evidence for robust coupling of their equilibrium conformations. Incorporation of a modified chromophore containing an electron-withdrawing cyano group to delocalize negative charge from the chromophore oxygen, analogous to the electronic rearrangement detected upon photon absorption, results in a lengthening of the Tyr-42 and Glu-46 hydrogen bonds and an attenuated hydrogen bond coupling. The results herein elucidate fundamental properties of hydrogen bonds within the complex environment of a protein interior. Furthermore, the robust conformational coupling and plasticity of hydrogen bonds observed in the PYP active site may facilitate the larger-scale dynamical coupling and signal transduction inherent to the biological function that PYP has evolved to carry out and may provide a model for other coupled dynamic systems.
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