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Wang H, Braun A, Cramer SP, Gee LB, Yoda Y. Nuclear Resonance Vibrational Spectroscopy: A Modern Tool to Pinpoint Site-Specific Cooperative Processes. Catalysts 2021; 11:909. [PMID: 35582460 PMCID: PMC9109880 DOI: 10.3390/cryst11080909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023] Open
Abstract
Nuclear resonant vibrational spectroscopy (NRVS) is a synchrotron radiation (SR)-based nuclear inelastic scattering spectroscopy that measures the phonons (i.e., vibrational modes) associated with the nuclear transition. It has distinct advantages over traditional vibration spectroscopy and has wide applications in physics, chemistry, bioinorganic chemistry, materials sciences, and geology, as well as many other research areas. In this article, we present a scientific and figurative description of this yet modern tool for the potential users in various research fields in the future. In addition to short discussions on its development history, principles, and other theoretical issues, the focus of this article is on the experimental aspects, such as the instruments, the practical measurement issues, the data process, and a few examples of its applications. The article concludes with introduction to non-57Fe NRVS and an outlook on the impact from the future upgrade of SR rings.
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Affiliation(s)
| | - Artur Braun
- Laboratory for High Performance Ceramics, Empa. Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland
| | | | - Leland B. Gee
- LCLS, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Yoshitaka Yoda
- Precision Spectroscopy Division, SPring-8/JASRI, Sayo 679-5198, Japan
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2
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Huang BC, Yang LW. Molecular dynamics simulations and linear response theories jointly describe biphasic responses of myoglobin relaxation and reveal evolutionarily conserved frequent communicators. Biophys Physicobiol 2020; 16:473-484. [PMID: 31984199 PMCID: PMC6975898 DOI: 10.2142/biophysico.16.0_473] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 09/20/2019] [Indexed: 12/01/2022] Open
Abstract
In this study, we provide a time-dependent mechanical model, taking advantage of molecular dynamics simulations, quasiharmonic analysis of molecular dynamics trajectories, and time-dependent linear response theories to describe vibrational energy redistribution within the protein matrix. The theoretical description explained the observed biphasic responses of specific residues in myoglobin to CO-photolysis and photoexcitation on heme. The fast responses were found to be triggered by impulsive forces and propagated mainly by principal modes <40 cm−1. The predicted fast responses for individual atoms were then used to study signal propagation within the protein matrix and signals were found to propagate ~8 times faster across helices (4076 m/s) than within the helices, suggesting the importance of tertiary packing in the sensitivity of proteins to external perturbations. We further developed a method to integrate multiple intramolecular signal pathways and discover frequent “communicators”. These communicators were found to be evolutionarily conserved including those distant from the heme.
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Affiliation(s)
- Bang-Chieh Huang
- Institute of Bioinformatics and Structural Biology, National Tsing-Hua University, Hsinchu 30013, Taiwan
| | - Lee-Wei Yang
- Institute of Bioinformatics and Structural Biology, National Tsing-Hua University, Hsinchu 30013, Taiwan.,Bioinformatics Program, Taiwan International Graduate Program, Institute of Information Sciences, Academia Sinica, Taipei 11529, Taiwan.,Department of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan.,Physics Division, National Center for Theoretical Sciences, Hsinchu 30013, Taiwan
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3
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Dauphas N, Hu MY, Baker EM, Hu J, Tissot FLH, Alp EE, Roskosz M, Zhao J, Bi W, Liu J, Lin JF, Nie NX, Heard A. SciPhon: a data analysis software for nuclear resonant inelastic X-ray scattering with applications to Fe, Kr, Sn, Eu and Dy. JOURNAL OF SYNCHROTRON RADIATION 2018; 25:1581-1599. [PMID: 30179200 PMCID: PMC6140397 DOI: 10.1107/s1600577518009487] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 07/02/2018] [Indexed: 06/01/2023]
Abstract
The synchrotron radiation technique of nuclear resonant inelastic X-ray scattering (NRIXS), also known as nuclear resonance vibrational spectroscopy or nuclear inelastic scattering, provides a wealth of information on the vibrational properties of solids. It has found applications in studies of lattice dynamics and elasticity, superconductivity, heme biochemistry, seismology, isotope geochemistry and many other fields. It involves probing the vibrational modes of solids by using the nuclear resonance of Mössbauer isotopes such as 57Fe, 83Kr, 119Sn, 151Eu and 161Dy. After data reduction, it provides the partial phonon density of states of the Mössbauer isotope that is investigated, as well as many other derived quantities such as the mean force constant of the chemical bonds and the Debye velocity. The data reduction is, however, not straightforward and involves removal of the elastic peak, normalization and Fourier-Log transformation. Furthermore, some of the quantities derived are highly sensitive to details in the baseline correction. A software package and several novel procedures to streamline and hopefully improve the reduction of the NRIXS data generated at sector 3ID of the Advanced Photon Source have been developed. The graphical user interface software is named SciPhon and runs as a Mathematica package. It is easily portable to other platforms and can be easily adapted for reducing data generated at other beamlines. Several tests and comparisons are presented that demonstrate the usefulness of this software, whose results have already been used in several publications. Here, the SciPhon software is used to reduce Kr, Sn, Eu and Dy NRIXS data, and potential implications for interpreting natural isotopic variations in those systems are discussed.
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Affiliation(s)
- Nicolas Dauphas
- Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60615, USA
| | - Michael Y. Hu
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA
| | - Erik M. Baker
- Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60615, USA
- Department of Earth and Planetary Sciences, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Justin Hu
- Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60615, USA
| | - Francois L. H. Tissot
- Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60615, USA
| | - E. Ercan Alp
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA
| | - Mathieu Roskosz
- IMPMC-UMR CNRS 7590, Sorbonne Universités, UPMC, IRD, MNHN, Muséum National d’Histoire Naturelle, 61 Rue Buffon, 75005 Paris, France
| | - Jiyong Zhao
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA
| | - Wenli Bi
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA
| | - Jin Liu
- Department of Geological Sciences, Stanford University, Stanford, CA, USA
| | - Jung-Fu Lin
- Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin, TX 78712, USA
| | - Nicole X. Nie
- Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60615, USA
| | - Andrew Heard
- Department of the Geophysical Sciences and Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60615, USA
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Domratcheva T, Schlichting I. Spiers Memorial Lecture. Introductory lecture: the impact of structure on photoinduced processes in nucleic acids and proteins. Faraday Discuss 2018; 207:9-26. [PMID: 29583144 DOI: 10.1039/c8fd00058a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Light is an important environmental variable and most organisms have evolved means to sense, exploit or avoid it and to repair detrimental effects on their genome. In general, light absorption is the task of specific chromophores, however other biomolecules such as oligonucleotides also do so which can result in undesired outcomes such as mutations and cancer. Given the biological importance of light-induced processes and applications for imaging, optogenetics, photodynamic therapy or photovoltaics, there is a great interest in understanding the detailed molecular mechanisms of photoinduced processes in proteins and nucleic acids. The processes are typically characterized by time-resolved spectroscopic approaches or computation, inferring structural information on transient species from stable ground state structures. Recently, however, structure determination of excited states or other short-lived species has become possible with the advent of X-ray free-electron lasers. This review gives an overview of the impact of structure on the understanding of photoinduced processes in macromolecules, focusing on systems presented at this Faraday Discussion meeting.
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Affiliation(s)
- Tatiana Domratcheva
- Max Planck Institute for Medical Research, Jahnstr. 29, 69120 Heidelberg, Germany.
| | - Ilme Schlichting
- Max Planck Institute for Medical Research, Jahnstr. 29, 69120 Heidelberg, Germany.
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5
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Abstract
For over 20 years, nuclear resonance vibrational spectroscopy (NRVS) has been used to study vibrational dynamics of iron-containing materials. With the only selection rule being iron motion, 57Fe NRVS has become an excellent tool to study iron-containing enzymes. Over the past decade, considerable progress has been made in the study of complex metalloenzymes using NRVS. Iron cofactors in heme-containing globins; [2Fe2S], [3Fe4S], [4Fe4S] proteins; the [NiFe] and [FeFe] hydrogenases; and nitrogenases have been explored in a fashion not possible through traditional vibrational spectroscopy. In this chapter, we discuss the basics of NRVS, a strategy to perform NRVS, and a discussion of the application of NRVS on rubredoxin and [FeFe] hydrogenase.
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Affiliation(s)
- Leland B Gee
- University of California, Davis, Davis, CA, United States.
| | - Hongxin Wang
- University of California, Davis, Davis, CA, United States
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6
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Scheidt WR, Li J, Sage JT. What Can Be Learned from Nuclear Resonance Vibrational Spectroscopy: Vibrational Dynamics and Hemes. Chem Rev 2017; 117:12532-12563. [PMID: 28921972 PMCID: PMC5639469 DOI: 10.1021/acs.chemrev.7b00295] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
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Nuclear resonance
vibrational spectroscopy (NRVS; also known as
nuclear inelastic scattering, NIS) is a synchrotron-based method that
reveals the full spectrum of vibrational dynamics for Mössbauer
nuclei. Another major advantage, in addition to its completeness (no
arbitrary optical selection rules), is the unique selectivity of NRVS.
The basics of this recently developed technique are first introduced
with descriptions of the experimental requirements and data analysis
including the details of mode assignments. We discuss the use of NRVS
to probe 57Fe at the center of heme and heme protein derivatives
yielding the vibrational density of states for the iron. The application
to derivatives with diatomic ligands (O2, NO, CO, CN–) shows the strong capabilities of identifying mode
character. The availability of the complete vibrational spectrum of
iron allows the identification of modes not available by other techniques.
This permits the correlation of frequency with other physical properties.
A significant example is the correlation we find between the Fe–Im
stretch in six-coordinate Fe(XO) hemes and the trans Fe–N(Im)
bond distance, not possible previously. NRVS also provides uniquely
quantitative insight into the dynamics of the iron. For example, it
provides a model-independent means of characterizing the strength
of iron coordination. Prediction of the temperature-dependent mean-squared
displacement from NRVS measurements yields a vibrational “baseline”
for Fe dynamics that can be compared with results from techniques
that probe longer time scales to yield quantitative insights into
additional dynamical processes.
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Affiliation(s)
- W Robert Scheidt
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556 United States
| | - Jianfeng Li
- College of Materials Science and Optoelectronic Technology, University of Chinese Academy of Sciences , YanQi Lake, HuaiRou District, Beijing 101408, China
| | - J Timothy Sage
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University , 120 Forsyth Street, Boston, Massachusetts 02115, United States
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7
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Félix G, Mikolasek M, Shepherd HJ, Long J, Larionova J, Guari Y, Itié JP, Chumakov AI, Nicolazzi W, Molnár G, Bousseksou A. Elasticity of Prussian-Blue-Analogue Nanoparticles. Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201700796] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Gautier Félix
- Institut Charles Gerhardt Montpellier; UMR 5253, Ingénierie Moléculaire et Nano-Objets; Université de Montpellier, ENSCM, CNRS; Place E. Bataillon 34095 Montpellier Cedex 5 France
| | - Mirko Mikolasek
- CS40220; ESRF - The European Synchrotron; 38043 Grenoble Cedex 9 France
| | - Helena J. Shepherd
- School of Physical Sciences; University of Kent; Park Wood Rd CT2 7NH Canterbury United Kingdom
| | - Jérôme Long
- Institut Charles Gerhardt Montpellier; UMR 5253, Ingénierie Moléculaire et Nano-Objets; Université de Montpellier, ENSCM, CNRS; Place E. Bataillon 34095 Montpellier Cedex 5 France
| | - Joulia Larionova
- Institut Charles Gerhardt Montpellier; UMR 5253, Ingénierie Moléculaire et Nano-Objets; Université de Montpellier, ENSCM, CNRS; Place E. Bataillon 34095 Montpellier Cedex 5 France
| | - Yannick Guari
- Institut Charles Gerhardt Montpellier; UMR 5253, Ingénierie Moléculaire et Nano-Objets; Université de Montpellier, ENSCM, CNRS; Place E. Bataillon 34095 Montpellier Cedex 5 France
| | - Jean-Paul Itié
- Synchrotron SOLEIL; L'Orme des Merisiers; Saint-Aubin 91192 Gif-sur-Yvette France
| | | | - William Nicolazzi
- Laboratoire de Chimie de Coordination; CNRS & Université de Toulouse (UPS, INP); 205 route de Narbonne 31077 Toulouse France
| | - Gábor Molnár
- Laboratoire de Chimie de Coordination; CNRS & Université de Toulouse (UPS, INP); 205 route de Narbonne 31077 Toulouse France
| | - Azzedine Bousseksou
- Laboratoire de Chimie de Coordination; CNRS & Université de Toulouse (UPS, INP); 205 route de Narbonne 31077 Toulouse France
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8
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Yoda Y, Okada K, Wang H, Cramer SP, Seto M. High-resolution monochromator for iron nuclear resonance vibrational spectroscopy of biological samples. JAPANESE JOURNAL OF APPLIED PHYSICS. PART 1, REGULAR PAPERS & SHORT NOTES 2016; 55:122401. [PMID: 29503983 PMCID: PMC5831540 DOI: 10.7567/jjap.55.122401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A new high-resolution monochromator for 14.4-keV X-rays has been designed and developed for the Fe nuclear resonance vibrational spectroscopy of biological samples. Higher flux and stability are especially important for measuring biological samples, because of the very weak signals produced due to the low concentrations of Fe-57. A 24% increase in flux while maintaining a high resolution below 0.9 meV is achieved in the calculation by adopting an asymmetric reflection of Ge, which is used as the first crystal of the three-bounce high-resolution monochromator. The small cost resulting from a 20% increase of the exit beam size is acceptable to our biological applications. The higher throughput of the new design has been experimentally verified. A fine rotation mechanics that that combines a weak-link hinge with a piezoelectric actuator was used for controlling the photon energy of the monochromatic beam. The resulting stability is sufficient to preserve the intrinsic resolution.
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Affiliation(s)
- Yoshitaka Yoda
- Japan Synchrotron Radiation Research Institute/SPring-8, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan
| | - Kyoko Okada
- Japan Synchrotron Radiation Research Institute/SPring-8, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan
| | - Hongxin Wang
- Department of Chemistry, University of California, 1 Shields Ave., Davis, CA, 95616, United States
- Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA, 94720, United States
| | - Stephen P. Cramer
- Department of Chemistry, University of California, 1 Shields Ave., Davis, CA, 95616, United States
- Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA, 94720, United States
| | - Makoto Seto
- Research Reactor Institute, Kyoto University, 2-1010 Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
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9
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Barends TRM, Foucar L, Ardevol A, Nass K, Aquila A, Botha S, Doak RB, Falahati K, Hartmann E, Hilpert M, Heinz M, Hoffmann MC, Köfinger J, Koglin JE, Kovacsova G, Liang M, Milathianaki D, Lemke HT, Reinstein J, Roome CM, Shoeman RL, Williams GJ, Burghardt I, Hummer G, Boutet S, Schlichting I. Direct observation of ultrafast collective motions in CO myoglobin upon ligand dissociation. Science 2015; 350:445-50. [PMID: 26359336 DOI: 10.1126/science.aac5492] [Citation(s) in RCA: 269] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 08/26/2015] [Indexed: 11/02/2022]
Abstract
The hemoprotein myoglobin is a model system for the study of protein dynamics. We used time-resolved serial femtosecond crystallography at an x-ray free-electron laser to resolve the ultrafast structural changes in the carbonmonoxy myoglobin complex upon photolysis of the Fe-CO bond. Structural changes appear throughout the protein within 500 femtoseconds, with the C, F, and H helices moving away from the heme cofactor and the E and A helices moving toward it. These collective movements are predicted by hybrid quantum mechanics/molecular mechanics simulations. Together with the observed oscillations of residues contacting the heme, our calculations support the prediction that an immediate collective response of the protein occurs upon ligand dissociation, as a result of heme vibrational modes coupling to global modes of the protein.
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Affiliation(s)
- Thomas R M Barends
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany.
| | - Lutz Foucar
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany
| | - Albert Ardevol
- Max-Planck-Institut für Biophysik, Max-von-Laue-Straße 3, 60438 Frankfurt am Main, Germany
| | - Karol Nass
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany
| | - Andrew Aquila
- European XFEL GmbH, Albert-Einstein-Ring 19, 22761 Hamburg, Germany
| | - Sabine Botha
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany
| | - R Bruce Doak
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany
| | - Konstantin Falahati
- Institut für Physikalische und Theoretische Chemie, Goethe-Universität, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Elisabeth Hartmann
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany
| | - Mario Hilpert
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany
| | - Marcel Heinz
- Max-Planck-Institut für Biophysik, Max-von-Laue-Straße 3, 60438 Frankfurt am Main, Germany. Institut für Physikalische und Theoretische Chemie, Goethe-Universität, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Matthias C Hoffmann
- Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Jürgen Köfinger
- Max-Planck-Institut für Biophysik, Max-von-Laue-Straße 3, 60438 Frankfurt am Main, Germany
| | - Jason E Koglin
- Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Gabriela Kovacsova
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany
| | - Mengning Liang
- Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Despina Milathianaki
- Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Henrik T Lemke
- Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Jochen Reinstein
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany
| | - Christopher M Roome
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany
| | - Robert L Shoeman
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany
| | - Garth J Williams
- Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Irene Burghardt
- Institut für Physikalische und Theoretische Chemie, Goethe-Universität, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Gerhard Hummer
- Max-Planck-Institut für Biophysik, Max-von-Laue-Straße 3, 60438 Frankfurt am Main, Germany
| | - Sébastien Boutet
- Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Ilme Schlichting
- Max-Planck-Institut für Medizinische Forschung, Jahnstraße 29, 69120 Heidelberg, Germany.
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10
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Chakraborty S, Reed J, Sage JT, Branagan NC, Petrik ID, Miner KD, Hu MY, Zhao J, Alp EE, Lu Y. Recent advances in biosynthetic modeling of nitric oxide reductases and insights gained from nuclear resonance vibrational and other spectroscopic studies. Inorg Chem 2015; 54:9317-29. [PMID: 26274098 PMCID: PMC4677664 DOI: 10.1021/acs.inorgchem.5b01105] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
This Forum Article focuses on recent
advances in structural and spectroscopic studies of biosynthetic models
of nitric oxide reductases (NORs). NORs are complex metalloenzymes
found in the denitrification pathway of Earth’s nitrogen cycle
where they catalyze the proton-dependent two-electron reduction of
nitric oxide (NO) to nitrous oxide (N2O). While much progress
has been made in biochemical and biophysical studies of native NORs
and their variants, a clear mechanistic understanding of this important
metalloenzyme related to its function is still elusive. We report
herein UV–vis and nuclear resonance vibrational spectroscopy
(NRVS) studies of mononitrosylated intermediates of the NOR reaction
of a biosynthetic model. The ability to selectively substitute metals
at either heme or nonheme metal sites allows the introduction of independent 57Fe probe atoms at either site, as well as allowing the preparation
of analogues of stable reaction intermediates by replacing either
metal with a redox inactive metal. Together with previous structural
and spectroscopic results, we summarize insights gained from studying
these biosynthetic models toward understanding structural features
responsible for the NOR activity and its mechanism. The outlook on
NOR modeling is also discussed, with an emphasis on the design of
models capable of catalytic turnovers designed based on close mimics
of the secondary coordination sphere of native NORs. New insights into nitric oxide reductases (NORs) are obtained. Using
nuclear resonance vibrational spectroscopy, we probe both iron atoms
in mononitrosylated intermediates of the NOR reaction in a biosynthetic
protein model that reveal new insights into the structural and electronic
features responsible for the NOR activity and its likely mechanism.
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Affiliation(s)
| | | | - J Timothy Sage
- Department of Physics, Northeastern University , Boston, Massachusetts 02115, United States
| | - Nicole C Branagan
- Department of Physics, Northeastern University , Boston, Massachusetts 02115, United States
| | | | | | - Michael Y Hu
- Advanced Photon Source, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Jiyong Zhao
- Advanced Photon Source, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - E Ercan Alp
- Advanced Photon Source, Argonne National Laboratory , Argonne, Illinois 60439, United States
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11
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Horch M, Hildebrandt P, Zebger I. Concepts in bio-molecular spectroscopy: vibrational case studies on metalloenzymes. Phys Chem Chem Phys 2015; 17:18222-37. [DOI: 10.1039/c5cp02447a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Challenges and chances in bio-molecular spectroscopy are exemplified by vibrational case studies on metalloenzymes.
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Affiliation(s)
- M. Horch
- Technische Universität Berlin
- Institut für Chemie
- D-10623 Berlin
- Germany
| | - P. Hildebrandt
- Technische Universität Berlin
- Institut für Chemie
- D-10623 Berlin
- Germany
| | - I. Zebger
- Technische Universität Berlin
- Institut für Chemie
- D-10623 Berlin
- Germany
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12
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Miller RJD. Mapping atomic motions with ultrabright electrons: the chemists' gedanken experiment enters the lab frame. Annu Rev Phys Chem 2014; 65:583-604. [PMID: 24423377 DOI: 10.1146/annurev-physchem-040412-110117] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This review documents the development of high-bunch charge electron pulses with sufficient combined spatiotemporal resolution and intensity to literally light up atomic motions. This development holds promise in coming to a first-principles understanding of diverse problems, ranging from molecular reaction dynamics and structure-function correlations in biology to cooperativity in strongly correlated electron-lattice systems. It is now possible to directly observe the key modes involved in propagating structural changes and the enormous reduction in dimensionality that occurs in barrier crossing regions, which is central to chemistry and makes reaction mechanisms transferrable concepts. This information will help direct theoretical advances that will undoubtedly lead to generalized principles with respect to scaling relations in structural dynamics that will bridge chemistry to biology. In this quest, the limitations and future directions for further development are discussed to give an overview of the present status of the field.
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Affiliation(s)
- R J Dwayne Miller
- Max Planck Institute for the Structure and Dynamics of Matter, Hamburg 22761, Germany, and Departments of Chemistry and Physics, University of Toronto, Toronto, Ontario M5S 3H6, Canada;
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13
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A practical guide for nuclear resonance vibrational spectroscopy (NRVS) of biochemical samples and model compounds. Methods Mol Biol 2014; 1122:125-37. [PMID: 24639257 DOI: 10.1007/978-1-62703-794-5_9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Nuclear resonance vibrational spectroscopy (NRVS) has been used by physicists for many years. However, it is still a relatively new technique for bioinorganic users. This technique yields a vibrational spectrum for a specific element, which can be easily interpreted. Furthermore, isotopic labeling allows for site-specific experiments. In this chapter, we discuss how to access specific beamlines, what kind of equipment is used in NRVS, and how the sample should be prepared and the data collected and analyzed.
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Leu BM, Zgierski MZ, Bischoff C, Li M, Hu MY, Zhao J, Martin SW, Alp EE, Scheidt WR. Quantitative vibrational dynamics of the metal site in a tin porphyrin: an IR, NRVS, and DFT study. Inorg Chem 2013; 52:9948-53. [PMID: 23962374 PMCID: PMC3787516 DOI: 10.1021/ic401152b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We used a newer, synchrotron-based, spectroscopic technique (nuclear resonance vibrational spectroscopy, NRVS) in combination with a more traditional one (infrared absorption, IR) to obtain a complete, quantitative picture of the metal center vibrational dynamics in a six-coordinated tin porphyrin. From the NRVS (119)Sn site-selectivity and the sensitivity of the IR signal to (112)Sn/(119)Sn isotope substitution, we identified the frequency of the antisymmetric stretching of the axial bonds (290 cm(-1)) and all the other vibrations involving Sn. Experimentally authenticated density functional theory (DFT) calculations aid the data interpretation by providing detailed normal mode descriptions for each observed vibration. These results may represent a starting point toward the characterization of the local vibrational dynamics of the metallic site in tin porphyrins and compounds with related structures. The quantitative complementariness between IR, NRVS, and DFT is emphasized.
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Affiliation(s)
- Bogdan M Leu
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States.
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15
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Kamali S, Wang H, Mitra D, Ogata H, Lubitz W, Manor BC, Rauchfuss TB, Byrne D, Bonnefoy V, Jenney FE, Adams MWW, Yoda Y, Alp E, Zhao J, Cramer SP. Observation of the Fe-CN and Fe-CO vibrations in the active site of [NiFe] hydrogenase by nuclear resonance vibrational spectroscopy. Angew Chem Int Ed Engl 2013; 52:724-8. [PMID: 23136119 PMCID: PMC3535562 DOI: 10.1002/anie.201204616] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 08/09/2012] [Indexed: 11/06/2022]
Abstract
Nuclear inelastic scattering of (57)Fe labeled [NiFe] hydrogenase is shown to give information on different states of the enzyme. It was thus possible to detect and assign Fe-CO and Fe-CN bending and stretching vibrations of the active site outside the spectral range of the Fe-S cluster normal modes.
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Affiliation(s)
- Saeed Kamali
- Department of Chemistry, University of California Davis, CA 95616 (USA)
| | - Hongxin Wang
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (USA)
- Department of Chemistry, University of California Davis, CA 95616 (USA)
| | - Devrani Mitra
- Department of Chemistry, University of California Davis, CA 95616 (USA)
| | - Hideaki Ogata
- Max-Planck-Institut für Chemische Energiekonversion 45470 Mülheim an der Ruhr (Germany)
| | - Wolfgang Lubitz
- Max-Planck-Institut für Chemische Energiekonversion 45470 Mülheim an der Ruhr (Germany)
| | - Brian C. Manor
- Department of Chemistry, University of Illinois Champaign-Urbana, IL 61801 (USA)
| | - Thomas B. Rauchfuss
- Department of Chemistry, University of Illinois Champaign-Urbana, IL 61801 (USA)
| | - Deborah Byrne
- Institut de Microbiologie de la Méditerranée Aix-Marseille-Universit , Marseille 13009 (France)
| | - Violaine Bonnefoy
- CNRS, IMM, Laboratoire de Chimie Bactérienne Marseille Cedex 20 (France)
| | - Francis E. Jenney
- Georgia Campus, Philadelphia College of Osteopathic Medicine Suwanee, GA 30024 (USA)
| | - Michael W. W. Adams
- Department of Biochemistry & Molecular Biology University of Georgia, Athens, GA 30602 (USA)
| | - Yoshitaka Yoda
- JASRI, SPring-8 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)
| | - Ercan Alp
- Advanced Photon Source, Argonne National Laboratory Argonne, IL 60439 (USA)
| | - Jiyong Zhao
- Advanced Photon Source, Argonne National Laboratory Argonne, IL 60439 (USA)
| | - Stephen P. Cramer
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (USA)
- Department of Chemistry, University of California Davis, CA 95616 (USA)
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Kamali S, Wang H, Mitra D, Ogata H, Lubitz W, Manor BC, Rauchfuss TB, Byrne D, Bonnefoy V, Jenney FE, Adams MWW, Yoda Y, Alp E, Zhao J, Cramer SP. Detektion von Fe-CN- und Fe-CO-Schwingungen im aktiven Zentrum der [NiFe]-Hydrogenase durch inelastische kernresonante Streuung. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201204616] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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17
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Guo Y, Brecht E, Aznavour K, Nix JC, Xiao Y, Wang H, George SJ, Bau R, Keable S, Peters JW, Adams MWW, Jenney F, Sturhahn W, Alp EE, Zhao J, Yoda Y, Cramer SP. Nuclear resonance vibrational spectroscopy (NRVS) of rubredoxin and MoFe protein crystals. ACTA ACUST UNITED AC 2012; 222:77-90. [PMID: 26052177 DOI: 10.1007/s10751-012-0643-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We have applied 57Fe nuclear resonance vibrational spectroscopy (NRVS) for the first time to study the dynamics of Fe centers in Fe-S protein crystals, including oxidized wild type rubredoxin crystals from Pyrococcus furiosus, and the MoFe protein of nitrogenase from Azotobacter vinelandii. Thanks to the NRVS selection rule, selectively probed vibrational modes have been observed in both oriented rubredoxin and MoFe protein crystals. The NRVS work was complemented by extended X-ray absorption fine structure spectroscopy (EXAFS) measurements on oxidized wild type rubredoxin crystals from Pyrococcus furiosus. The EXAFS spectra revealed the Fe-S bond length difference in oxidized Pf Rd protein, which is qualitatively consistent with the X-ray crystal structure.
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Affiliation(s)
- Yisong Guo
- Department of Applied Science, University of California, Davis, CA 95616
| | - Eric Brecht
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717
| | - Kristen Aznavour
- Department of Chemistry, University of Southern California, Los Angeles, CA 90033
| | - Jay C Nix
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Yuming Xiao
- Department of Applied Science, University of California, Davis, CA 95616
| | - Hongxin Wang
- Department of Applied Science, University of California, Davis, CA 95616 ; Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Simon J George
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Robert Bau
- Department of Chemistry, University of Southern California, Los Angeles, CA 90033
| | - Stephen Keable
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717
| | - John W Peters
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717
| | | | - Francis Jenney
- Georgia Campus, Philadelphia College of Osteopathic Medicine, Suwanee, GA 30024
| | - Wolfgang Sturhahn
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439
| | - Ercan E Alp
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439
| | - Jiyong Zhao
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439
| | - Yoshitaka Yoda
- JASRI, SPring-8, 1-1-1 Kouto, Mikazuki-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - Stephen P Cramer
- Department of Applied Science, University of California, Davis, CA 95616 ; Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 ; Department of Chemistry, University of California, Davis, CA 95616
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Hałas A, Orzechowska A, Derrien V, Chumakov AI, Sebban P, Fiedor J, Lipińska M, Zając M, Ślęzak T, Strzałka K, Matlak K, Korecki J, Fiedor L, Burda K. The dynamics of the non-heme iron in bacterial reaction centers from Rhodobacter sphaeroides. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2012; 1817:2095-102. [PMID: 22921693 DOI: 10.1016/j.bbabio.2012.08.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Revised: 08/06/2012] [Accepted: 08/09/2012] [Indexed: 11/28/2022]
Abstract
We investigate the dynamical properties of the non-heme iron (NHFe) in His-tagged photosynthetic bacterial reaction centers (RCs) isolated from Rhodobacter (Rb.) sphaeroides. Mössbauer spectroscopy and nuclear inelastic scattering of synchrotron radiation (NIS) were applied to monitor the arrangement and flexibility of the NHFe binding site. In His-tagged RCs, NHFe was stabilized only in a high spin ferrous state. Its hyperfine parameters (IS=1.06±0.01mm/s and QS=2.12±0.01mm/s), and Debye temperature (θ(D0)~167K) are comparable to those detected for the high spin state of NHFe in non-His-tagged RCs. For the first time, pure vibrational modes characteristic of NHFe in a high spin ferrous state are revealed. The vibrational density of states (DOS) shows some maxima between 22 and 33meV, 33 and 42meV, and 53 and 60meV and a very sharp one at 44.5meV. In addition, we observe a large contribution of vibrational modes at low energies. This iron atom is directly connected to the protein matrix via all its ligands, and it is therefore extremely sensitive to the collective motions of the RC protein core. A comparison of the DOS spectra of His-tagged and non-His-tagged RCs from Rb. sphaeroides shows that in the latter case the spectrum was overlapped by the vibrations of the heme iron of residual cytochrome c(2), and a low spin state of NHFe in addition to its high spin one. This enabled us to pin-point vibrations characteristic for the low spin state of NHFe.
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Affiliation(s)
- A Hałas
- AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, al. Mickiewicza 30, 30-059 Kraków, Poland
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Moeser B, Janoschka A, Wolny JA, Paulsen H, Filippov I, Berry RE, Zhang H, Chumakov AI, Walker FA, Schünemann V. Nuclear inelastic scattering and Mössbauer spectroscopy as local probes for ligand binding modes and electronic properties in proteins: vibrational behavior of a ferriheme center inside a β-barrel protein. J Am Chem Soc 2012; 134:4216-28. [PMID: 22295945 DOI: 10.1021/ja210067t] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In this work, we present a study of the influence of the protein matrix on its ability to tune the binding of small ligands such as NO, cyanide (CN(-)), and histamine to the ferric heme iron center in the NO-storage and -transport protein Nitrophorin 2 (NP2) from the salivary glands of the blood-sucking insect Rhodnius prolixus. Conventional Mössbauer spectroscopy shows a diamagnetic ground state of the NP2-NO complex and Type I and II electronic ground states of the NP2-CN(-) and NP2-histamine complex, respectively. The change in the vibrational signature of the protein upon ligand binding has been monitored by Nuclear Inelastic Scattering (NIS), also called Nuclear Resonant Vibrational Spectroscopy (NRVS). The NIS data thus obtained have also been calculated by quantum mechanical (QM) density functional theory (DFT) coupled with molecular mechanics (MM) methods. The calculations presented here show that the heme ruffling in NP2 is a consequence of the interaction with the protein matrix. Structure optimizations of the heme and its ligands with DFT retain the characteristic saddling and ruffling only if the protein matrix is taken into account. Furthermore, simulations of the NIS data by QM/MM calculations suggest that the pH dependence of the binding of NO, but not of CN(-) and histamine, might be a consequence of the protonation state of the heme carboxyls.
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Affiliation(s)
- Beate Moeser
- Technische Universität Kaiserslautern, Fachbereich Physik, Erwin-Schrödinger-Str. 56, D-67663 Kaiserslautern, Germany
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20
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Hu C, Barabanschikov A, Ellison MK, Zhao J, Alp EE, Sturhahn W, Zgierski MZ, Sage JT, Scheidt WR. Nuclear resonance vibrational spectra of five-coordinate imidazole-ligated iron(II) porphyrinates. Inorg Chem 2012; 51:1359-70. [PMID: 22243131 PMCID: PMC3273671 DOI: 10.1021/ic201580v] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nuclear resonance vibrational spectra have been obtained for six five-coordinate imidazole-ligated iron(II) porphyrinates, [Fe(Por)(L)] (Por = tetraphenylporphyrinate, octaethylporphyrinate, tetratolylporphyrinate, or protoporphyrinate IX and L = 2-methylimidazole or 1,2-dimethylimidazole). Measurements have been made on both powder and oriented crystal samples. The spectra are dominated by strong signals around 200-300 cm(-1). Although the in-plane and out-of-plane vibrations are seriously overlapped, oriented crystal spectra allow their deconvolution. Thus, oriented crystal experimental data, along with density functional theory (DFT) calculations, enable the assignment of key vibrations in the spectra. Molecular dynamics are also discussed. The nature of the Fe-N(Im) vibrations has been elaborated further than was possible from resonance Raman studies. Our study suggests that the Fe motions are coupled with the porphyrin core and peripheral groups motions. Both peripheral groups and their conformations have significant influence on the vibrational spectra (position and shape).
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Affiliation(s)
- Chuanjiang Hu
- Contribution from Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P.R. China
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Alexander Barabanschikov
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, Massachusetts 02115
| | - Mary K. Ellison
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
| | - Jiyong Zhao
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439
| | - E. Ercan Alp
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439
| | - Wolfgang Sturhahn
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439
| | - Marek Z. Zgierski
- Steacie Institute for Molecular Science, National Research Council of Canada, Ottawa, Ontario, Canada KIA OR6
| | - J. Timothy Sage
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, Massachusetts 02115
| | - W. Robert Scheidt
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556
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Jayasooriya UA, Peck JN, Elaine Barclay J, Hardy SM, Chumakov AI, Evans DJ, Pickett CJ, Oganesyan VS. Nuclear inelastic scattering spectroscopy of tris(acetylacetonate)iron(III); A vibrational probe via the iron atom. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.10.063] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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Paulsen H, Trautwein AX, Wegner P, Schmidt C, Chumakov AI, Schünemann V. Interpretation of Nuclear Resonant Vibrational Spectra of Rubredoxin Using a Combined Quantum Mechanics and Molecular Mechanics Approach. Chemphyschem 2011; 12:3434-41. [DOI: 10.1002/cphc.201100595] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Indexed: 11/06/2022]
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Barabanschikov A, Demidov A, Kubo M, Champion PM, Sage JT, Zhao J, Sturhahn W, Alp EE. Spectroscopic identification of reactive porphyrin motions. J Chem Phys 2011; 135:015101. [PMID: 21744919 PMCID: PMC3144962 DOI: 10.1063/1.3598473] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2011] [Accepted: 05/18/2011] [Indexed: 11/14/2022] Open
Abstract
Nuclear resonance vibrational spectroscopy (NRVS) reveals the vibrational dynamics of a Mössbauer probe nucleus. Here, (57)Fe NRVS measurements yield the complete spectrum of Fe vibrations in halide complexes of iron porphyrins. Iron porphine serves as a useful symmetric model for the more complex spectrum of asymmetric heme molecules that contribute to numerous essential biological processes. Quantitative comparison with the vibrational density of states (VDOS) predicted for the Fe atom by density functional theory calculations unambiguously identifies the correct sextet ground state in each case. These experimentally authenticated calculations then provide detailed normal mode descriptions for each observed vibration. All Fe-ligand vibrations are clearly identified despite the high symmetry of the Fe environment. Low frequency molecular distortions and acoustic lattice modes also contribute to the experimental signal. Correlation matrices compare vibrations between different molecules and yield a detailed picture of how heme vibrations evolve in response to (a) halide binding and (b) asymmetric placement of porphyrin side chains. The side chains strongly influence the energetics of heme doming motions that control Fe reactivity, which are easily observed in the experimental signal.
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Affiliation(s)
- Alexander Barabanschikov
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, Massachusetts 02115, USA
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Guo J, Budarz T, Ward JM, Prohofsky EW. Dynamical transition in proteins and non-Gaussian behavior of low-frequency modes in self-consistent normal mode analysis. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2010; 82:041917. [PMID: 21230323 DOI: 10.1103/physreve.82.041917] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 07/22/2010] [Indexed: 05/30/2023]
Abstract
Self-consistent normal mode analysis (SCNMA) is applied to heme c type cytochrome f to study temperature-dependent protein motion. Classical normal mode analysis assumes harmonic behavior and the protein mean-square displacement has a linear dependence on temperature. This is only consistent with low-temperature experimental results. To connect the protein vibrational motions between low and physiological temperatures, we have incorporated a fitted set of anharmonic potentials into SCNMA. In addition, quantum harmonic-oscillator theory has been used to calculate the displacement distribution for individual vibrational modes. We find that the modes involving soft bonds exhibit significant non-Gaussian dynamics at physiological temperature, which suggests that it may be the cause of the non-Gaussian behavior of the protein motions probed by elastic incoherent neutron scattering. The combined theory displays a dynamical transition caused by the softening of few "torsional" modes in the low-frequency regime ( <50 cm(-1) or <6 meV or >0.6 ps). These modes change from Gaussian to a classical distribution upon heating. Our theory provides an alternative way to understand the microscopic origin of the protein dynamical transition.
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Affiliation(s)
- Jianguang Guo
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA
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Scheidt WR, Barabanschikov A, Pavlik JW, Silvernail NJ, Sage JT. Electronic structure and dynamics of nitrosyl porphyrins. Inorg Chem 2010; 49:6240-52. [PMID: 20666384 PMCID: PMC2919577 DOI: 10.1021/ic100261b] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Nitric oxide (NO) is a signaling molecule employed to regulate essential physiological processes. Thus, there is great interest in understanding the interaction of NO with heme, which is found at the active site of many proteins that recognize NO, as well as those involved in its creation and elimination. We summarize what we have learned from investigations of the structure, vibrational properties, and conformational dynamics of NO complexes with ferrous porphyrins, as well as computational investigations in support of these experimental studies. Multitemperature crystallographic data reveal variations in the orientational disorder of the nitrosyl ligand. In some cases, equilibria among NO orientations can be analyzed using the van't Hoff relationship and the free energy and enthalpy of the solid-state transitions evaluated experimentally. Density functional theory (DFT) calculations predict that intrinsic barriers to torsional rotation are smaller than thermal energies at physiological temperatures, and the coincidence of observed NO orientations with minima in molecular mechanics potentials indicates that nonbonded interactions with other chemical groups control the conformational freedom of the bound NO. In favorable cases, reduced disorder at low temperatures exposes subtle structural features including off-axis tilting of the Fe-NO bond and anisotropy of the equatorial Fe-N bonds. We also present the results of nuclear resonance vibrational spectroscopy measurements on oriented single crystals of [Fe(TPP)(NO)] and [Fe(TPP)(1-MeIm)(NO)]. These describe the anisotropic vibrational motion of iron in five- and six-coordinate heme-NO complexes and reveal vibrations of all Fe-ligand bonds as well as low-frequency molecular distortions associated with the doming of the heme upon ligand binding. A quantitative comparison with predicted frequencies, amplitudes, and directions facilitates identification of the vibrational modes but also suggests that commonly used DFT functionals are not fully successful at capturing the trans interaction between the axial NO and imidazole ligands. This supports previous conclusions that heme-NO complexes exhibit an unusual degree of variability with respect to the computational method, and we speculate that this variability hints at a genuine electronic instability that a protein can exploit to tune its reactivity. We anticipate that ongoing characterization of heme-NO complexes will deepen our understanding of their structure, dynamics, and reactivity.
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Affiliation(s)
- W. Robert Scheidt
- To whom correspondence should be addressed: WRS: , Fax (574) 631-6652; JTS , FAX (617)-373-2943
| | | | | | | | - J. Timothy Sage
- To whom correspondence should be addressed: WRS: , Fax (574) 631-6652; JTS , FAX (617)-373-2943
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Lipińska M, Orzechowska A, Fiedor J, Chumakov AI, Ślȩzak T, Zaja̧c M, Matlak K, Korecki J, Hałas A, Strzałka K, Fiedor L, Burda K. Influence of Cd2+on the spin state of non-heme iron and on protein local motions in reactions centers from purple photosynthetic bacteriumRhodospirilium rubrum. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/217/1/012021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Xiao Y, Tan ML, Ichiye T, Wang H, Guo Y, Smith MC, Meyer J, Sturhahn W, Alp EE, Zhao J, Yoda Y, Cramer SP. Dynamics of Rhodobacter capsulatus [2FE-2S] ferredoxin VI and Aquifex aeolicus ferredoxin 5 via nuclear resonance vibrational spectroscopy (NRVS) and resonance Raman spectroscopy. Biochemistry 2010; 47:6612-27. [PMID: 18512953 DOI: 10.1021/bi701433m] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have used (57)Fe nuclear resonance vibrational spectroscopy (NRVS) to study the Fe(2)S(2)(Cys)(4) sites in oxidized and reduced [2Fe-2S] ferredoxins from Rhodobacter capsulatus (Rc FdVI) and Aquifex aeolicus (Aa Fd5). In the oxidized forms, nearly identical NRVS patterns are observed, with strong bands from Fe-S stretching modes peaking around 335 cm(-1), and additional features observed as high as the B(2u) mode at approximately 421 cm(-1). Both forms of Rc FdVI have also been investigated by resonance Raman (RR) spectroscopy. There is good correspondence between NRVS and Raman frequencies, but because of different selection rules, intensities vary dramatically between the two kinds of spectra. For example, the B(3u) mode at approximately 288 cm(-1), attributed to an asymmetric combination of the two FeS(4) breathing modes, is often the strongest resonance Raman feature. In contrast, it is nearly invisible in the NRVS, as there is almost no Fe motion in such FeS(4) breathing. NRVS and RR analysis of isotope shifts with (36)S-substituted into bridging S(2-) ions in Rc FdVI allowed quantitation of S(2-) motion in different normal modes. We observed the symmetric Fe-Fe stretching mode at approximately 190 cm(-1) in both NRVS and RR spectra. At still lower energies, the NRVS presents a complex envelope of bending, torsion, and protein modes, with a maximum at 78 cm(-1). The (57)Fe partial vibrational densities of states (PVDOS) were interpreted by normal-mode analysis with optimization of Urey-Bradley force fields. Progressively more complex D(2h) Fe(2)S(2)S'(4), C(2h) Fe(2)S(2)(SCC)(4), and C(1) Fe(2)S(2)(Cys)(4) models were optimized by comparison with the experimental spectra. After modification of the CHARMM22 all-atom force field by the addition of refined Fe-S force constants, a simulation employing the complete protein structure was used to reproduce the PVDOS, with better results in the low frequency protein mode region. This process was then repeated for analysis of data on the reduced FdVI. Finally, the degree of collectivity was used to quantitate the delocalization of the dynamic properties of the redox-active Fe site. The NRVS technique demonstrates great promise for the observation and quantitative interpretation of the dynamical properties of Fe-S proteins.
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Affiliation(s)
- Yuming Xiao
- Department of Applied Science, University of California, Davis, California 95616, USA
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Baumgartner F, Helm H. Stark field control of nonadiabatic dynamics in triatomic hydrogen. PHYSICAL REVIEW LETTERS 2010; 104:103002. [PMID: 20366418 DOI: 10.1103/physrevlett.104.103002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Indexed: 05/29/2023]
Abstract
We show experimentally that an external electric field can be used to control the amplitudes of nonadiabatic paths taken by a dissociating molecule. In the example presented here, this control is achieved by Stark-field mixing in H(3) Rydberg states with different decay paths. The final state continuum is in each path formed by three-particle wave packets of slow neutral hydrogen atoms in their electronic ground state. Their momentum vector correlations show signs of interference, since the molecule can access the identical continuum via two distinctly different paths, involving different nonadiabatic coupling mechanisms. As an added feature a preferred alignment of the fragmentation plane in the laboratory frame emerges, corresponding to a selective dissociation of molecules oriented along the field direction.
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Affiliation(s)
- Frank Baumgartner
- Department of Physics, University of Freiburg, Stefan-Meier-Strasse 19, D-79104 Freiburg, Germany
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Leu BM, Ching TH, Zhao J, Sturhahn W, Alp EE, Sage JT. Vibrational dynamics of iron in cytochrome C. J Phys Chem B 2009; 113:2193-200. [PMID: 19173569 DOI: 10.1021/jp806574t] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nuclear resonance vibrational spectroscopy (NRVS) and Raman spectroscopy on (54)Fe- and (57)Fe-enriched cytochrome c (cyt c) identify multiple bands involving vibrations of the heme Fe. Comparison with predictions from Fe isotope shifts reveals that 70% of the NRVS signal in the 300-450 cm(-1) frequency range corresponds to vibrations resolved in Soret-enhanced Raman spectra. This frequency range dominates the "stiffness", an effective force constant determined by the Fe vibrational density of states (VDOS), which measures the strength of nearest-neighbor interactions with Fe. The stiffness of the low-spin Fe environment in both oxidation states of cyt c significantly exceeds that for the high-spin Fe in deoxymyoglobin, where the 200-300 cm(-1) frequency range dominates the VDOS. This situation is reflected in the shorter Fe-ligand bond lengths in the former with respect to the latter. The longer Fe-S(Met80) in oxidized cyt c with respect to reduced cyt c leads to a decrease in the stiffness of the iron environment upon oxidation. Comparison with NRVS measurements allows us to assess assignments for vibrational modes resolved in this region of the heme Raman spectrum. We consider the possibility that the 372 cm(-1) band in reduced cyt c involves the Fe-S(Met80) bond.
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Affiliation(s)
- Bogdan M Leu
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, Massachusetts 02115, USA
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30
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Zhang Y, Straub JE. Diversity of solvent dependent energy transfer pathways in heme proteins. J Phys Chem B 2009; 113:825-30. [PMID: 19115811 DOI: 10.1021/jp807499y] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The time scales and pathways of heme cooling in both reduced cytochrome c and oxidized cytochrome c following heme photoexcitation were studied using molecular dynamics simulation. Five different solvent models, including normal water, heavy water, normal glycerol, deuterated glycerol, and a nonpolar solvent, were used in the simulation. Single exponential decay of the excess kinetic energy of the heme following photoexcitation was observed in all systems studied. The simulated time scale for heme cooling in normal water agrees with recent experimental results. In contrast to heme cooling in myoglobin, no solvent dependence was observed for the time scale for heme cooling in cytochrome c. The diversity of solvent dependence results from the different local heme environments in the two proteins. In myoglobin, it has been established that the dominant mechanism for heme cooling is direct energy transfer from the heme to the solvent. In cytochrome c, direct interaction between heme and protein residues forms the dominant energy transfer pathway. This distinction is dictated by protein topology and linked to function.
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Affiliation(s)
- Yong Zhang
- Department of Chemistry, Boston University, Boston, Massachusetts, 02215, USA
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31
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Zhang Y, Fujisaki H, Straub JE. Mode-Specific Vibrational Energy Relaxation of Amide I′ and II′ Modes in N-Methylacetamide/Water Clusters: Intra- and Intermolecular Energy Transfer Mechanisms. J Phys Chem A 2009; 113:3051-60. [DOI: 10.1021/jp8109995] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Yong Zhang
- Department of Chemistry, Boston University, Boston, Massachusetts 02215
| | - Hiroshi Fujisaki
- Department of Chemistry, Boston University, Boston, Massachusetts 02215
| | - John E. Straub
- Department of Chemistry, Boston University, Boston, Massachusetts 02215
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32
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Zhang Y, Straub JE. Direct evidence for mode-specific vibrational energy relaxation from quantum time-dependent perturbation theory. II. The ν4 and ν7 modes of iron-protoporphyrin IX and iron porphine. J Chem Phys 2009; 130:095102. [DOI: 10.1063/1.3086080] [Citation(s) in RCA: 8] [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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33
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Zhang Y, Fujisaki H, Straub JE. Direct evidence for mode-specific vibrational energy relaxation from quantum time-dependent perturbation theory. I. Five-coordinate ferrous iron porphyrin model. J Chem Phys 2009; 130:025102. [DOI: 10.1063/1.3055277] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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34
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Leu BM, Zhang Y, Bu L, Straub JE, Zhao J, Sturhahn W, Alp EE, Sage JT. Resilience of the iron environment in heme proteins. Biophys J 2008; 95:5874-89. [PMID: 18835904 PMCID: PMC2599821 DOI: 10.1529/biophysj.108.138198] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Accepted: 07/22/2008] [Indexed: 11/18/2022] Open
Abstract
Conformational flexibility is essential to the functional behavior of proteins. We use an effective force constant introduced by Zaccai, the resilience, to quantify this flexibility. Site-selective experimental and computational methods allow us to determine the resilience of heme protein active sites. The vibrational density of states of the heme Fe determined using nuclear resonance vibrational spectroscopy provides a direct experimental measure of the resilience of the Fe environment, which we compare quantitatively with values derived from the temperature dependence of atomic mean-squared displacements in molecular dynamics simulations. Vibrational normal modes in the THz frequency range dominate the resilience. Both experimental and computational methods find a higher resilience for cytochrome c than for myoglobin, which we attribute to the increased number of covalent links to the peptide in the former protein. For myoglobin, the resilience of the iron environment is larger than the average resilience previously determined for hydrogen sites using neutron scattering. Experimental results suggest a slightly reduced resilience for cytochrome c upon oxidation, although the change is smaller than reported in previous Mössbauer investigations on a bacterial cytochrome c, and is not reproduced by the simulations. Oxidation state also has no significant influence on the compressibility calculated for cyt c, although a slightly larger compressibility is predicted for myoglobin.
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Affiliation(s)
- Bogdan M Leu
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, Massachusetts, USA
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35
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Asthalter T, Rajagopalan S, Kauf T, Rabe V, Christoffers J. Monitoring Reaction Intermediates in the FeCl3-Catalyzed Michael Reaction by Nuclear Inelastic Scattering. J Phys Chem A 2008; 112:11514-8. [DOI: 10.1021/jp806878x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- T. Asthalter
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, and Institut für Reine and Angewandte Chemie, Carl-von-Ossietzky-Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, D-26111 Oldenburg, Germany
| | - S. Rajagopalan
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, and Institut für Reine and Angewandte Chemie, Carl-von-Ossietzky-Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, D-26111 Oldenburg, Germany
| | - Th. Kauf
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, and Institut für Reine and Angewandte Chemie, Carl-von-Ossietzky-Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, D-26111 Oldenburg, Germany
| | - V. Rabe
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, and Institut für Reine and Angewandte Chemie, Carl-von-Ossietzky-Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, D-26111 Oldenburg, Germany
| | - J. Christoffers
- Institut für Physikalische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany, and Institut für Reine and Angewandte Chemie, Carl-von-Ossietzky-Universität Oldenburg, Carl-von-Ossietzky-Strasse 9-11, D-26111 Oldenburg, Germany
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36
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Kubo M, Gruia F, Benabbas A, Barabanschikov A, Montfort WR, Maes EM, Champion PM. Low-frequency mode activity of heme: femtosecond coherence spectroscopy of iron porphine halides and nitrophorin. J Am Chem Soc 2008; 130:9800-11. [PMID: 18597456 PMCID: PMC2765994 DOI: 10.1021/ja800916d] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The low-frequency mode activity of metalloporphyrins has been studied for iron porphine-halides (Fe(P)(X), X = Cl, Br) and nitrophorin 4 (NP4) using femtosecond coherence spectroscopy (FCS) in combination with polarized resonance Raman spectroscopy and density functional theory (DFT). It is confirmed that the mode symmetry selection rules for FCS are the same as for Raman scattering and that both Franck-Condon and Jahn-Teller mode activities are observed for Fe(P)(X) under Soret resonance conditions. The DFT-calculated low-frequency (20-400 cm (-1)) modes, and their frequency shifts upon halide substitution, are in good agreement with experimental Raman and coherence data, so that mode assignments can be made. The doming mode is located at approximately 80 cm (-1) for Fe(P)(Cl) and at approximately 60 cm (-1) for Fe(P)(Br). NP4 is also studied with coherence techniques, and the NO-bound species of ferric and ferrous NP4 display a mode at approximately 30-40 cm (-1) that is associated with transient heme doming motion following NO photolysis. The coherence spectra of three ferric derivatives of NP4 with different degrees of heme ruffling distortion are also investigated. We find a mode at approximately 60 cm (-1) whose relative intensity in the coherence spectra depends quadratically on the magnitude of the ruffling distortion. To quantitatively account for this correlation, a new "distortion-induced" Raman enhancement mechanism is presented. This mechanism is unique to low-frequency "soft modes" of the molecular framework that can be distorted by environmental forces. These results demonstrate the potential of FCS as a sensitive probe of dynamic and functionally important nonplanar heme vibrational excitations that are induced by the protein environmental forces or by the chemical reactions in the aqueous phase.
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Affiliation(s)
- Minoru Kubo
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, Massachusetts 02115, USA
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37
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George SJ, Igarashi RY, Xiao Y, Hernandez JA, Demuez M, Zhao D, Yoda Y, Ludden PW, Rubio LM, Cramer SP. Extended X-ray absorption fine structure and nuclear resonance vibrational spectroscopy reveal that NifB-co, a FeMo-co precursor, comprises a 6Fe core with an interstitial light atom. J Am Chem Soc 2008; 130:5673-80. [PMID: 18386899 DOI: 10.1021/ja0755358] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
NifB-co, an Fe-S cluster produced by the enzyme NifB, is an intermediate on the biosynthetic pathway to the iron molybdenum cofactor (FeMo-co) of nitrogenase. We have used Fe K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy together with (57)Fe nuclear resonance vibrational spectroscopy (NRVS) to probe the structure of NifB-co while bound to the NifX protein from Azotobacter vinelandii. The spectra have been interpreted in part by comparison with data for the completed FeMo-co attached to the NafY carrier protein: the NafY:FeMo-co complex. EXAFS analysis of the NifX:NifB-co complex yields an average Fe-S distance of 2.26 A and average Fe-Fe distances of 2.66 and 3.74 A. Search profile analyses reveal the presence of a single Fe-X (X = C, N, or O) interaction at 2.04 A, compared to a 2.00 A Fe-X interaction found in the NafY:FeMo-co EXAFS. This suggests that the interstitial light atom (X) proposed to be present in FeMo-co has already inserted at the NifB-co stage of biosynthesis. The NRVS exhibits strong bands from Fe-S stretching modes peaking around 270, 315, 385, and 408 cm(-1). Additional intensity at approximately 185-200 cm(-1) is interpreted as a set of cluster "breathing" modes similar to those seen for the FeMo-cofactor. The strength and location of these modes also suggest that the FeMo-co interstitial light atom seen in the crystal structure is already in place in NifB-co. Both the EXAFS and NRVS data for NifX:NifB-co are best simulated using a Fe 6S 9X trigonal prism structure analogous to the 6Fe core of FeMo-co, although a 7Fe structure made by capping one trigonal 3S terminus with Fe cannot be ruled out. The results are consistent with the conclusion that the interstitial light atom is already present at an early stage in FeMo-co biosynthesis prior to the incorporation of Mo and R-homocitrate.
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Affiliation(s)
- Simon J George
- Advanced Biological and Environmental X-ray Facility, Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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38
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Investigations of vibrational coherence in the low-frequency region of ferric heme proteins. Biophys J 2007; 94:2252-68. [PMID: 18065461 DOI: 10.1529/biophysj.107.122119] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Femtosecond coherence spectroscopy is applied to a series of ferric heme protein samples. The low-frequency vibrational spectra that are revealed show dominant oscillations near 40 cm(-1). MbCN is taken as a typical example of a histidine-ligated, six-coordinate, ferric heme and a comprehensive spectroscopic analysis is carried out. The results of this analysis reveal a new heme photoproduct species, absorbing near 418 nm, which is consistent with the photolysis of the His(93) axial ligand. The photoproduct undergoes subsequent rebinding/recovery with a time constant of approximately 4 ps. The photoproduct lineshapes are consistent with a photolysis quantum yield of 75-100%, although the observation of a relatively strong six-coordinate heme coherence near 252 cm(-1) (assigned to nu(9) in the MbCN Raman spectrum) suggests that the 75% lower limit is much more likely. The phase and amplitude excitation profiles of the low-frequency mode at 40 cm(-1) suggest that this mode is strongly coupled to the MbCN photoproduct species and it is assigned to the doming mode of the transient penta-coordinated material. The absolute phase of the 40 cm(-1) mode is found to be pi/2 on the red side of 418 nm and it jumps to 3pi/2 as excitation is tuned to the blue side of 418 nm. The absolute phase of the 40 cm(-1) signal is not explained by the standard theory for resonant impulsive stimulated Raman scattering. New mechanisms that give a dominant momentum impulse to the resonant wavepacket, rather than a coordinate displacement, are discussed. The possibilities of heme iron atom recoil after photolysis, as well as ultrafast nonradiative decay, are explored as potential ways to generate the strong momentum impulse needed to understand the phase properties of the 40 cm(-1) mode.
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39
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Gruia F, Ye X, Ionascu D, Kubo M, Champion PM. Low frequency spectral density of ferrous heme: perturbations induced by axial ligation and protein insertion. Biophys J 2007; 93:4404-13. [PMID: 17766351 PMCID: PMC2098722 DOI: 10.1529/biophysj.107.114736] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Femtosecond coherence spectroscopy is used to probe low frequency (20-400 cm(-1)) modes of the ferrous heme group in solution, with and without 2-methyl imidazole (2MeIm) as an axial ligand. The results are compared to heme proteins (CPO, P450(cam), HRP, Mb) where insertion of the heme into the protein results in redistribution of the low frequency spectral density and in (approximately 60%) longer damping times for the coherent signals. The major effect of imidazole ligation to the ferrous heme is the "softening" of the low frequency force constants by a factor of approximately 0.6 +/- 0.1. The functional consequences of imidazole ligation are assessed and it is found that the enthalpic CO rebinding barrier is increased significantly when imidazole is bound. The force constant softening analysis, combined with the kinetics results, indicates that the iron is displaced by only approximately 0.2 A from the heme plane in the absence of the imidazole ligand, whereas it is displaced by approximately 0.4 A when imidazole (histidine) is present. This suggests that binding of imidazole (histidine) as an axial ligand, and the concomitant softening of the force constants, leads to an anharmonic distortion of the heme group that has significant functional consequences.
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Affiliation(s)
- Flaviu Gruia
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, Massachusetts, USA
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40
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Rai BK, Prohofsky EW, Durbin SM. Single-atom test of all-atom empirical potentials: Fe in myoglobin. J Phys Chem B 2007; 109:18983-7. [PMID: 16853444 DOI: 10.1021/jp052950i] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The measured Fe vibrational density of states in deoxy-myoglobin, obtained from nuclear resonance vibrational spectroscopy, is compared to results from a normal-mode analysis using an all-atom empirical potential. Substantial disagreement reveals that for this one atom, the empirical potential does not accurately describe the actual forces. A Green function technique is developed to calculate the iron vibrational spectrum of deoxy-myoglobin by coupling the independently calculated heme and globin normal modes; nonbonded interactions between the heme molecule and the protein are essential for a good fit to the measurements. A projection of the eigenvectors from this potential onto the displacements induced by binding of CO demonstrates that normal modes over a broad range centered around 50-150 cm(-1) may drive the ligand-induced structural changes.
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Affiliation(s)
- Brajesh K Rai
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA
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41
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Leu BM, Silvernail NJ, Zgierski MZ, Wyllie GRA, Ellison MK, Scheidt WR, Zhao J, Sturhahn W, Alp EE, Sage JT. Quantitative vibrational dynamics of iron in carbonyl porphyrins. Biophys J 2007; 92:3764-83. [PMID: 17350996 PMCID: PMC1868970 DOI: 10.1529/biophysj.106.093773] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We use nuclear resonance vibrational spectroscopy and computational predictions based on density functional theory (DFT) to explore the vibrational dynamics of (57)Fe in porphyrins that mimic the active sites of histidine-ligated heme proteins complexed with carbon monoxide. Nuclear resonance vibrational spectroscopy yields the complete vibrational spectrum of a Mössbauer isotope, and provides a valuable probe that is not only selective for protein active sites but quantifies the mean-squared amplitude and direction of the motion of the probe nucleus, in addition to vibrational frequencies. Quantitative comparison of the experimental results with DFT calculations provides a detailed, rigorous test of the vibrational predictions, which in turn provide a reliable description of the observed vibrational features. In addition to the well-studied stretching vibration of the Fe-CO bond, vibrations involving the Fe-imidazole bond, and the Fe-N(pyr) bonds to the pyrrole nitrogens of the porphyrin contribute prominently to the observed experimental signal. All of these frequencies show structural sensitivity to the corresponding bond lengths, but previous studies have failed to identify the latter vibrations, presumably because the coupling to the electronic excitation is too small in resonance Raman measurements. We also observe the FeCO bending vibrations, which are not Raman active for these unhindered model compounds. The observed Fe amplitude is strongly inconsistent with three-body oscillator descriptions of the FeCO fragment, but agrees quantitatively with DFT predictions. Over the past decade, quantum chemical calculations have suggested revised estimates of the importance of steric distortion of the bound CO in preventing poisoning of heme proteins by carbon monoxide. Quantitative agreement with the predicted frequency, amplitude, and direction of Fe motion for the FeCO bending vibrations provides direct experimental support for the quantum chemical description of the energetics of the FeCO unit.
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Affiliation(s)
- Bogdan M Leu
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, Massachusetts, USA
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42
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Tan ML, Bizzarri AR, Xiao Y, Cannistraro S, Ichiye T, Manzoni C, Cerullo G, Adams MWW, Jenney FE, Cramer SP. Observation of terahertz vibrations in Pyrococcus furiosus rubredoxin via impulsive coherent vibrational spectroscopy and nuclear resonance vibrational spectroscopy – interpretation by molecular mechanics. J Inorg Biochem 2007; 101:375-84. [PMID: 17204331 DOI: 10.1016/j.jinorgbio.2006.09.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2006] [Revised: 09/28/2006] [Accepted: 09/29/2006] [Indexed: 10/24/2022]
Abstract
We have used impulsive coherent vibrational spectroscopy (ICVS) to study the Fe(S-Cys)(4) site in oxidized rubredoxin (Rd) from Pyrococcus furiosus (Pf). In this experiment, a 15 fs visible laser pulse is used to coherently pump the sample to an excited electronic state, and a second <10 fs pulse is used to probe the change in transmission as a function of the time delay. PfRd was observed to relax to the ground state by a single exponential decay with time constants of approximately 255-275 fs. Superimposed on this relaxation are oscillations caused by coherent excitation of vibrational modes in both excited and ground electronic states. Fourier transformation reveals the frequencies of these modes. The strongest ICV mode with 570 nm excitation is the symmetric Fe-S stretching mode near 310 cm(-1), compared to 313 cm(-1) in the low temperature resonance Raman. If the rubredoxin is pumped at 520 nm, a set of strong bands occurs between 20 and 110 cm(-1). Finally, there is a mode at approximately 500 cm(-1) which is similar to features near 508 cm(-1) in blue Cu proteins that have been attributed to excited state vibrations. Normal mode analysis using 488 protein atoms and 558 waters gave calculated spectra that are in good agreement with previous nuclear resonance vibrational spectra (NRVS) results. The lowest frequency normal modes are identified as collective motions of the entire protein or large segments of polypeptide. Motion in these modes may affect the polar environment of the redox site and thus tune the electron transfer functions in rubredoxins.
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Affiliation(s)
- Ming-Liang Tan
- Department of Applied Science, University of California, Davis, CA 95616, USA
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43
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Adams KL, Tsoi S, Yan J, Durbin SM, Ramdas AK, Cramer WA, Sturhahn W, Alp EE, Schulz C. Fe vibrational spectroscopy of myoglobin and cytochrome f. J Phys Chem B 2006; 110:530-6. [PMID: 16471565 DOI: 10.1021/jp053440r] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Fe vibrational density of states (VDOS) has been determined for the heme proteins deoxymyoglobin, metmyoglobin, and cytochrome f in the oxidized and reduced states, using nuclear resonance vibrational spectroscopy (NRVS). For cytochrome f in particular, the NRVS spectrum is compared with multiwavelength resonance Raman spectra to identify those Raman modes with significant Fe displacement. Modes not seen by Raman due to optical selection rules appear in the NRVS spectrum. The mean Fe force constant extracted from the VDOS illustrates how Fe dynamics varies among these four monoheme proteins, and is correlated with oxidation and spin state trends seen in model heme compounds. The protein's contribution to Fe motion is dominant at low frequencies, where coupling to the backbone tightly constrains Fe displacements in cytochrome f, in contrast to enhanced heme flexibility in myoglobin.
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Affiliation(s)
- Kristl L Adams
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA
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44
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Asthalter T. Nuclear Inelastic Scattering on Ferrocene-Based Rotator Phases: Theoryvs.Experiment. Z PHYS CHEM 2006. [DOI: 10.1524/zpch.2006.220.7.979] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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45
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Abstract
Third generation synchrotron light sources provide stable, tuneable light of energy up to the hard X-ray region. The gain of a trillion in brightness as compared to a conventional laboratory X-ray source transforms the opportunities for establishing structure-function relationships. The light may be quasi-continuous or pulsed, have controllable polarisation and have coherence lengths larger than the sample size. The high brightness provides a basis for adding time and spatial resolution to X-ray scattering and spectroscopy. It may also be used to identify very specific information about the magnetic properties of atoms within materials, element specific vibrations, and local structural descriptions identified with chemical speciation. More demanding scattering and diffraction problems can be solved such as weakly scattering materials, large unit cells and structural entities. The high collimation of the source also provides enhanced spectroscopic and diffraction resolution that gives more insight into molecular, extended and supramolecular structures. The length scales can be bridged from the atomic up to that of visible light microscopy and buried features within materials can be observed with the appropriate energy. With an increased emphasis on ease of use, such capabilities are open to exploitation for chemical challenges.
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Affiliation(s)
- John Evans
- School of Chemistry, University of Southampton, Southampton, SO17 1BJ, UK.
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46
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Leu BM, Timothy Sage J, Zgierski MZ, Wyllie GRA, Ellison MK, Robert Scheidt W, Sturhahn W, Ercan Alp E, Durbin SM. Vibrational Dynamics of Biological Molecules: Multi-quantum Contributions. THE JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS 2005; 66:2250-2256. [PMID: 16894397 PMCID: PMC1513645 DOI: 10.1016/j.jpcs.2005.09.075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
High-resolution X-ray measurements near a nuclear resonance reveal the complete vibrational spectrum of the probe nucleus. Because of this, nuclear resonance vibrational spectroscopy (NRVS) is a uniquely quantitative probe of the vibrational dynamics of reactive iron sites in proteins and other complex molecules. Our measurements of vibrational fundamentals have revealed both frequencies and amplitudes of (57)Fe vibrations in proteins and model compounds. Information on the direction of Fe motion has also been obtained from measurements on oriented single crystals, and provides an essential test of normal mode predictions. Here, we report the observation of weaker two-quantum vibrational excitations (overtones and combinations) for compounds that mimic the active site of heme proteins. The predicted intensities depend strongly on the direction of Fe motion. We compare the observed features with predictions based on the observed fundamentals, using information on the direction of Fe motion obtained either from DFT predictions or from single crystal measurements. Two-quantum excitations may become a useful tool to identify the directions of the Fe oscillations when single crystals are not available.
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Affiliation(s)
- Bogdan M Leu
- Steacie Institute for Molecular Science, National Research Council of Canada, Ottawa, Ontario, Canada K1A OR6
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47
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Zeng W, Silvernail NJ, Wharton DC, Georgiev GY, Leu BM, Scheidt WR, Zhao J, Sturhahn W, Alp EE, Sage JT. Direct probe of iron vibrations elucidates NO activation of heme proteins. J Am Chem Soc 2005; 127:11200-1. [PMID: 16089422 PMCID: PMC1502376 DOI: 10.1021/ja051052x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We use nuclear resonance vibrational spectroscopy (NRVS) to identify the Fe-NO stretching frequency in the NO adduct of myoglobin (MbNO) and in the related six-coordinate porphyrin Fe(TPP)(1-MeIm)(NO). Frequency shifts observed in MbNO Raman spectra upon isotopic substitution of Fe or the nitrosyl nitrogen confirm and extend the NRVS results. In contrast with previous assignments, the Fe-NO frequency of these six-coordinate complexes lies 70-100 cm-1 lower than in the analogous five-coordinate nitrosyl complexes, indicating a significant weakening of the Fe-NO bond in the presence of a trans imidazole ligand. This result supports proposed mechanisms for NO activation of heme proteins and underscores the value of NRVS as a direct probe of metal reactivity in complex biomolecules.
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Affiliation(s)
- Weiqiao Zeng
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, Massachusetts 02115, USA
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48
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Nagy AM, Raicu V, Miller RJD. Nonlinear optical studies of heme protein dynamics: Implications for proteins as hybrid states of matter. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2005; 1749:148-72. [PMID: 15927874 DOI: 10.1016/j.bbapap.2005.02.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2004] [Revised: 02/03/2005] [Accepted: 02/15/2005] [Indexed: 10/25/2022]
Abstract
Protein structure is fundamentally related to function. However, static structures alone are insufficient to understand how a protein works. Dynamics play an equally important role. Given that proteins are highly associated aperiodic systems, it may be expected that protein dynamics would follow glass-like dynamics. However, protein functions occur on time scales orders of magnitude faster than the time scales typically associated with glassy systems. It is becoming clear that the reaction forces driving functions do not sample entirely the large number of configurations available to a protein but are highly directed along an optimized pathway. Could there be any correlation between specific topological features in protein structures and dynamics that leads to strongly correlated atomic displacements in the dynamical response to a perturbation? This review will try to provide an answer by focusing upon recent nonlinear optical studies with the aim of directly observing functionally important protein motions over the entire dynamic range of the protein response function. The specific system chosen is photoinduced dynamics of ligand dissociation at the active site in heme proteins, with myoglobin serving as the simplest model system. The energetics and nuclear motions from the very earliest events involved in bond breaking on the femtosecond time scale all the way out to ligand escape and bimolecular rebinding on the microsecond and millisecond time scale have been mapped out. The picture that is emerging is that the system consists of strongly coupled motions from the very instant the bond breaks at the active site that cascade into low frequency collective modes specific to the protein structure. It is this coupling that imparts the ability of a protein to function on time scales more commensurate with liquids while simultaneously conserving structural integrity akin to solids.
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Affiliation(s)
- A M Nagy
- Department of Chemistry, University of Toronto, Ontario, Canada
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49
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Leu BM, Zgierski MZ, Wyllie GRA, Scheidt WRE, Sturhahn W, Alp EE, Durbin SM, Sage JT. Quantitative vibrational dynamics of iron in nitrosyl porphyrins. J Am Chem Soc 2004; 126:4211-27. [PMID: 15053610 PMCID: PMC1570756 DOI: 10.1021/ja038526h] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We use quantitative experimental and theoretical approaches to characterize the vibrational dynamics of the Fe atom in porphyrins designed to model heme protein active sites. Nuclear resonance vibrational spectroscopy (NRVS) yields frequencies, amplitudes, and directions for 57Fe vibrations in a series of ferrous nitrosyl porphyrins, which provide a benchmark for evaluation of quantum chemical vibrational calculations. Detailed normal mode predictions result from DFT calculations on ferrous nitrosyl tetraphenylporphyrin Fe(TPP)(NO), its cation [Fe(TPP)(NO)]+, and ferrous nitrosyl porphine Fe(P)(NO). Differing functionals lead to significant variability in the predicted Fe-NO bond length and frequency for Fe(TPP)(NO). Otherwise, quantitative comparison of calculated and measured Fe dynamics on an absolute scale reveals good overall agreement, suggesting that DFT calculations provide a reliable guide to the character of observed Fe vibrational modes. These include a series of modes involving Fe motion in the plane of the porphyrin, which are rarely identified using infrared and Raman spectroscopies. The NO binding geometry breaks the four-fold symmetry of the Fe environment, and the resulting frequency splittings of the in-plane modes predicted for Fe(TPP)(NO) agree with observations. In contrast to expectations of a simple three-body model, mode energy remains localized on the FeNO fragment for only two modes, an N-O stretch and a mode with mixed Fe-NO stretch and FeNO bend character. Bending of the FeNO unit also contributes to several of the in-plane modes, but no primary FeNO bending mode is identified for Fe(TPP)(NO). Vibrations associated with hindered rotation of the NO and heme doming are predicted at low frequencies, where Fe motion perpendicular to the heme is identified experimentally at 73 and 128 cm-1. Identification of the latter two modes is a crucial first step toward quantifying the reactive energetics of Fe porphyrins and heme proteins.
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Affiliation(s)
- Bogdan M. Leu
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, MA 02115
| | - Marek Z. Zgierski
- Steacie Institute for Molecular Science, National Research Council of Canada, Ottawa, Ontario, Canada K1A OR6
| | - Graeme R. A. Wyllie
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556
| | - W. Rob ert Scheidt
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556
| | - Wolfgang Sturhahn
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439
| | - E. Ercan Alp
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439
| | | | - J. Timothy Sage
- Department of Physics and Center for Interdisciplinary Research on Complex Systems, Northeastern University, Boston, MA 02115
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