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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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Pump-Probe Time-Resolved Serial Femtosecond Crystallography at X-Ray Free Electron Lasers. CRYSTALS 2020. [DOI: 10.3390/cryst10070628] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
With time-resolved crystallography (TRX), it is possible to follow the reaction dynamics in biological macromolecules by investigating the structure of transient states along the reaction coordinate. X-ray free electron lasers (XFELs) have enabled TRX experiments on previously uncharted femtosecond timescales. Here, we review the recent developments, opportunities, and challenges of pump-probe TRX at XFELs.
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3
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Šrajer V, Schmidt M. Watching Proteins Function with Time-resolved X-ray Crystallography. JOURNAL OF PHYSICS D: APPLIED PHYSICS 2017; 50:373001. [PMID: 29353938 PMCID: PMC5771432 DOI: 10.1088/1361-6463/aa7d32] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Macromolecular crystallography was immensely successful in the last two decades. To a large degree this success resulted from use of powerful third generation synchrotron X-ray sources. An expansive database of more than 100,000 protein structures, of which many were determined at resolution better than 2 Å, is available today. With this achievement, the spotlight in structural biology is shifting from determination of static structures to elucidating dynamic aspects of protein function. A powerful tool for addressing these aspects is time-resolved crystallography, where a genuine biological function is triggered in the crystal with a goal of capturing molecules in action and determining protein kinetics and structures of intermediates (Schmidt et al., 2005a; Schmidt 2008; Neutze and Moffat, 2012; Šrajer 2014). In this approach, short and intense X-ray pulses are used to probe intermediates in real time and at room temperature, in an ongoing reaction that is initiated synchronously and rapidly in the crystal. Time-resolved macromolecular crystallography with 100 ps time resolution at synchrotron X-ray sources is in its mature phase today, particularly for studies of reversible, light-initiated reactions. The advent of the new free electron lasers for hard X-rays (XFELs; 5-20 keV), which provide exceptionally intense, femtosecond X-ray pulses, marks a new frontier for time-resolved crystallography. The exploration of ultra-fast events becomes possible in high-resolution structural detail, on sub-picosecond time scales (Tenboer et al., 2014; Barends et al., 2015; Pande et al., 2016). We review here state-of-the-art time-resolved crystallographic experiments both at synchrotrons and XFELs. We also outline challenges and further developments necessary to broaden the application of these methods to many important proteins and enzymes of biomedical relevance.
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Affiliation(s)
- Vukica Šrajer
- Center for Advanced Radiation Sources, The University of Chicago, Chicago, IL, USA
| | - Marius Schmidt
- Physics Department, University of Wisconsin-Milwaukee, Milwaukee, IL, USA
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4
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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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5
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Abstract
Time-resolved macromolecular crystallography unifies protein structure determination with chemical kinetics. With the advent of fourth generation X-ray sources the time-resolution can be on the order of 10-40 fs, which opens the ultrafast time scale to structure determination. Fundamental motions and transitions associated with chemical reactions in proteins can now be observed. Moreover, new experimental approaches at synchrotrons allow for the straightforward investigation of all kind of reactions in biological macromolecules. Here, recent developments in the field are reviewed.
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Affiliation(s)
- Marius Schmidt
- Kenwood Interdisciplinary Research Complex, Physics Department, University of Wisconsin-Milwaukee, Room 3087, 3135 North Maryland Avenue, Milwaukee, WI, 53211, USA.
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6
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Hutchison CD, Kaucikas M, Tenboer J, Kupitz C, Moffat K, Schmidt M, van Thor JJ. Photocycle populations with femtosecond excitation of crystalline photoactive yellow protein. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.04.087] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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7
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Pande K, Hutchison CDM, Groenhof G, Aquila A, Robinson JS, Tenboer J, Basu S, Boutet S, DePonte DP, Liang M, White TA, Zatsepin NA, Yefanov O, Morozov D, Oberthuer D, Gati C, Subramanian G, James D, Zhao Y, Koralek J, Brayshaw J, Kupitz C, Conrad C, Roy-Chowdhury S, Coe JD, Metz M, Xavier PL, Grant TD, Koglin JE, Ketawala G, Fromme R, Šrajer V, Henning R, Spence JCH, Ourmazd A, Schwander P, Weierstall U, Frank M, Fromme P, Barty A, Chapman HN, Moffat K, van Thor JJ, Schmidt M. Femtosecond structural dynamics drives the trans/cis isomerization in photoactive yellow protein. Science 2016; 352:725-9. [PMID: 27151871 DOI: 10.1126/science.aad5081] [Citation(s) in RCA: 290] [Impact Index Per Article: 36.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 04/05/2016] [Indexed: 11/02/2022]
Abstract
A variety of organisms have evolved mechanisms to detect and respond to light, in which the response is mediated by protein structural changes after photon absorption. The initial step is often the photoisomerization of a conjugated chromophore. Isomerization occurs on ultrafast time scales and is substantially influenced by the chromophore environment. Here we identify structural changes associated with the earliest steps in the trans-to-cis isomerization of the chromophore in photoactive yellow protein. Femtosecond hard x-ray pulses emitted by the Linac Coherent Light Source were used to conduct time-resolved serial femtosecond crystallography on photoactive yellow protein microcrystals over a time range from 100 femtoseconds to 3 picoseconds to determine the structural dynamics of the photoisomerization reaction.
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Affiliation(s)
- Kanupriya Pande
- Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA. Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany
| | | | - Gerrit Groenhof
- Nanoscience Center and Department of Chemistry, University of Jyväskylä, Post Office Box 35, 40014 Jyväskylä, Finland
| | - Andy Aquila
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Josef S Robinson
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Jason Tenboer
- Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
| | - Shibom Basu
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287, USA
| | - Sébastien Boutet
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Daniel P DePonte
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Mengning Liang
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Thomas A White
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany
| | - Nadia A Zatsepin
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Oleksandr Yefanov
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany
| | - Dmitry Morozov
- Nanoscience Center and Department of Chemistry, University of Jyväskylä, Post Office Box 35, 40014 Jyväskylä, Finland
| | - Dominik Oberthuer
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany
| | - Cornelius Gati
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany
| | | | - Daniel James
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Yun Zhao
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Jake Koralek
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Jennifer Brayshaw
- Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
| | - Christopher Kupitz
- Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
| | - Chelsie Conrad
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287, USA
| | - Shatabdi Roy-Chowdhury
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287, USA
| | - Jesse D Coe
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287, USA
| | - Markus Metz
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany
| | - Paulraj Lourdu Xavier
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany. IMPRS-UFAST, Max Planck Institute for Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Thomas D Grant
- Hauptman-Woodward Institute, State University of New York at Buffalo, 700 Ellicott Street, Buffalo, NY 14203, USA
| | - Jason E Koglin
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Sand Hill Road, Menlo Park, CA 94025, USA
| | - Gihan Ketawala
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287, USA
| | - Raimund Fromme
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287, USA
| | - Vukica Šrajer
- 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
| | - John C H Spence
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Abbas Ourmazd
- Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
| | - Peter Schwander
- Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
| | - Uwe Weierstall
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Matthias Frank
- Lawrence Livermore National Laboratory, Livermore, CA 94550, USA
| | - Petra Fromme
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287, USA
| | - Anton Barty
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany
| | - Henry N Chapman
- Center for Free Electron Laser Science, Deutsches Elektronen Synchrotron, Notkestrasse 85, 22607 Hamburg, Germany. Center for Ultrafast Imaging, University of Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - 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, Department of Life Sciences, Imperial College, London SW7 2AZ, UK
| | - Marius Schmidt
- Department of Physics, University of Wisconsin-Milwaukee, Milwaukee, WI 53211, USA
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8
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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: 327] [Impact Index Per Article: 32.7] [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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9
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Schmidt M, Srajer V, Henning R, Ihee H, Purwar N, Tenboer J, Tripathi S. Protein energy landscapes determined by five-dimensional crystallography. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2013; 69:2534-42. [PMID: 24311594 PMCID: PMC3852658 DOI: 10.1107/s0907444913025997] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 09/19/2013] [Indexed: 02/20/2023]
Abstract
Free-energy landscapes decisively determine the progress of enzymatically catalyzed reactions [Cornish-Bowden (2012), Fundamentals of Enzyme Kinetics, 4th ed.]. Time-resolved macromolecular crystallography unifies transient-state kinetics with structure determination [Moffat (2001), Chem. Rev. 101, 1569-1581; Schmidt et al. (2005), Methods Mol. Biol. 305, 115-154; Schmidt (2008), Ultrashort Laser Pulses in Medicine and Biology] because both can be determined from the same set of X-ray data. Here, it is demonstrated how barriers of activation can be determined solely from five-dimensional crystallography, where in addition to space and time, temperature is a variable as well [Schmidt et al. (2010), Acta Cryst. A66, 198-206]. Directly linking molecular structures with barriers of activation between them allows insight into the structural nature of the barrier to be gained. Comprehensive time series of crystallographic data at 14 different temperature settings were analyzed and the entropy and enthalpy contributions to the barriers of activation were determined. One hundred years after the discovery of X-ray scattering, these results advance X-ray structure determination to a new frontier: the determination of energy landscapes.
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Affiliation(s)
- Marius Schmidt
- Physics Department, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA
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