51
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Jeon H, Hong S. Peroxide Bond Cleavage of Nonheme Iron-(Hydro/Alkyl)Peroxo Complexes Induced by Endogenous and Exogenous Factors. CHEM LETT 2019. [DOI: 10.1246/cl.180831] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Hyeri Jeon
- Department of Chemistry, Sookmyung Women’s University, Seoul 04310, Korea
| | - Seungwoo Hong
- Department of Chemistry, Sookmyung Women’s University, Seoul 04310, Korea
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52
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Weitz AC, Mills MR, Ryabov AD, Collins TJ, Guo Y, Bominaar EL, Hendrich MP. A Synthetically Generated LFe IVOH n Complex. Inorg Chem 2019; 58:2099-2108. [PMID: 30667223 DOI: 10.1021/acs.inorgchem.8b03200] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
High-valent Fe-OH species are important intermediates in hydroxylation chemistry. Such complexes have been implicated in mechanisms of oxygen-activating enzymes and have thus far been observed in Compound II of sulfur-ligated heme enzymes like cytochrome P450. Attempts to synthetically model such species have thus far seen relatively little success. Here, the first synthetic FeIVOH n complex has been generated and spectroscopically characterized as either [LFeIVOH]- or [LFeIVOH2]0, where H4L = Me4C2(NHCOCMe2NHCO)2CMe2 is a variant of a tetra-amido macrocyclic ligand (TAML). The steric bulk provided by the replacement of the aryl group with the -CMe2CMe2- unit in this TAML variant prevents dimerization in all oxidation states over a wide pH range, thus allowing the generation of FeIVOH n in near quantitative yield from oxidation of the [LFeIIIOH2]- precursor.
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Affiliation(s)
- Andrew C Weitz
- Department of Chemistry , Carnegie Mellon University , 4400 Fifth Avenue , Pittsburgh , Pennsylvania 15213 , United States
| | - Matthew R Mills
- Department of Chemistry , Carnegie Mellon University , 4400 Fifth Avenue , Pittsburgh , Pennsylvania 15213 , United States
| | - Alexander D Ryabov
- Department of Chemistry , Carnegie Mellon University , 4400 Fifth Avenue , Pittsburgh , Pennsylvania 15213 , United States
| | - Terrence J Collins
- Department of Chemistry , Carnegie Mellon University , 4400 Fifth Avenue , Pittsburgh , Pennsylvania 15213 , United States
| | - Yisong Guo
- Department of Chemistry , Carnegie Mellon University , 4400 Fifth Avenue , Pittsburgh , Pennsylvania 15213 , United States
| | - Emile L Bominaar
- Department of Chemistry , Carnegie Mellon University , 4400 Fifth Avenue , Pittsburgh , Pennsylvania 15213 , United States
| | - Michael P Hendrich
- Department of Chemistry , Carnegie Mellon University , 4400 Fifth Avenue , Pittsburgh , Pennsylvania 15213 , United States
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53
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Ashkar R, Bilheux HZ, Bordallo H, Briber R, Callaway DJE, Cheng X, Chu XQ, Curtis JE, Dadmun M, Fenimore P, Fushman D, Gabel F, Gupta K, Herberle F, Heinrich F, Hong L, Katsaras J, Kelman Z, Kharlampieva E, Kneller GR, Kovalevsky A, Krueger S, Langan P, Lieberman R, Liu Y, Losche M, Lyman E, Mao Y, Marino J, Mattos C, Meilleur F, Moody P, Nickels JD, O'Dell WB, O'Neill H, Perez-Salas U, Peters J, Petridis L, Sokolov AP, Stanley C, Wagner N, Weinrich M, Weiss K, Wymore T, Zhang Y, Smith JC. Neutron scattering in the biological sciences: progress and prospects. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2018; 74:1129-1168. [PMID: 30605130 DOI: 10.1107/s2059798318017503] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 12/12/2018] [Indexed: 12/11/2022]
Abstract
The scattering of neutrons can be used to provide information on the structure and dynamics of biological systems on multiple length and time scales. Pursuant to a National Science Foundation-funded workshop in February 2018, recent developments in this field are reviewed here, as well as future prospects that can be expected given recent advances in sources, instrumentation and computational power and methods. Crystallography, solution scattering, dynamics, membranes, labeling and imaging are examined. For the extraction of maximum information, the incorporation of judicious specific deuterium labeling, the integration of several types of experiment, and interpretation using high-performance computer simulation models are often found to be particularly powerful.
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Affiliation(s)
- Rana Ashkar
- Department of Physics, Virginia Polytechnic Institute and State University, 850 West Campus Drive, Blacksburg, VA 24061, USA
| | - Hassina Z Bilheux
- Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | | | - Robert Briber
- Materials Science and Engineeering, University of Maryland, 1109 Chemical and Nuclear Engineering Building, College Park, MD 20742, USA
| | - David J E Callaway
- Department of Chemistry and Biochemistry, The City College of New York, 160 Convent Avenue, New York, NY 10031, USA
| | - Xiaolin Cheng
- Department of Medicinal Chemistry and Pharmacognosy, Ohio State University College of Pharmacy, 642 Riffe Building, Columbus, OH 43210, USA
| | - Xiang Qiang Chu
- Graduate School of China Academy of Engineering Physics, Beijing, 100193, People's Republic of China
| | - Joseph E Curtis
- NIST Center for Neutron Research, National Institutes of Standard and Technology, 100 Bureau Drive, Mail Stop 6102, Gaithersburg, MD 20899, USA
| | - Mark Dadmun
- Department of Chemistry, University of Tennessee Knoxville, Knoxville, TN 37996, USA
| | - Paul Fenimore
- Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - David Fushman
- Department of Chemistry and Biochemistry, Center for Biomolecular Structure and Organization, University of Maryland, College Park, MD 20742, USA
| | - Frank Gabel
- Institut Laue-Langevin, Université Grenoble Alpes, CEA, CNRS, IBS, 38042 Grenoble, France
| | - Kushol Gupta
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Frederick Herberle
- Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Frank Heinrich
- NIST Center for Neutron Research, National Institutes of Standard and Technology, 100 Bureau Drive, Mail Stop 6102, Gaithersburg, MD 20899, USA
| | - Liang Hong
- Department of Physics and Astronomy, Institute of Natural Sciences, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - John Katsaras
- Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Zvi Kelman
- Institute for Bioscience and Biotechnology Research, National Institute of Standards and Technology and the University of Maryland, Rockville, MD 20850, USA
| | - Eugenia Kharlampieva
- Department of Chemistry, University of Alabama at Birmingham, 901 14th Street South, Birmingham, AL 35294, USA
| | - Gerald R Kneller
- Centre de Biophysique Moléculaire, CNRS, Université d'Orléans, Chateau de la Source, Avenue du Parc Floral, Orléans, France
| | - Andrey Kovalevsky
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Susan Krueger
- NIST Center for Neutron Research, National Institutes of Standard and Technology, 100 Bureau Drive, Mail Stop 6102, Gaithersburg, MD 20899, USA
| | - Paul Langan
- Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Raquel Lieberman
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Yun Liu
- NIST Center for Neutron Research, National Institutes of Standard and Technology, 100 Bureau Drive, Mail Stop 6102, Gaithersburg, MD 20899, USA
| | - Mathias Losche
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
| | - Edward Lyman
- Department of Physics and Astrophysics, University of Delaware, Newark, DE 19716, USA
| | - Yimin Mao
- NIST Center for Neutron Research, National Institutes of Standard and Technology, 100 Bureau Drive, Mail Stop 6102, Gaithersburg, MD 20899, USA
| | - John Marino
- Institute for Bioscience and Biotechnology Research, National Institute of Standards and Technology and the University of Maryland, Rockville, MD 20850, USA
| | - Carla Mattos
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts, USA
| | - Flora Meilleur
- Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Peter Moody
- Leicester Institute of Structural and Chemical Biology, Department of Molecular and Cell Biology, University of Leicester, Leicester LE1 9HN, England
| | - Jonathan D Nickels
- Department of Physics, Virginia Polytechnic Institute and State University, 850 West Campus Drive, Blacksburg, VA 24061, USA
| | - William B O'Dell
- Institute for Bioscience and Biotechnology Research, National Institute of Standards and Technology and the University of Maryland, Rockville, MD 20850, USA
| | - Hugh O'Neill
- Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Ursula Perez-Salas
- Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | | | - Loukas Petridis
- Materials Science and Engineeering, University of Maryland, 1109 Chemical and Nuclear Engineering Building, College Park, MD 20742, USA
| | - Alexei P Sokolov
- Department of Chemistry, University of Tennessee Knoxville, Knoxville, TN 37996, USA
| | - Christopher Stanley
- Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Norman Wagner
- Department of Chemistry and Biochemistry, The City College of New York, 160 Convent Avenue, New York, NY 10031, USA
| | - Michael Weinrich
- NIST Center for Neutron Research, National Institutes of Standard and Technology, 100 Bureau Drive, Mail Stop 6102, Gaithersburg, MD 20899, USA
| | - Kevin Weiss
- Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Troy Wymore
- Graduate School of China Academy of Engineering Physics, Beijing, 100193, People's Republic of China
| | - Yang Zhang
- NIST Center for Neutron Research, National Institutes of Standard and Technology, 100 Bureau Drive, Mail Stop 6102, Gaithersburg, MD 20899, USA
| | - Jeremy C Smith
- Department of Medicinal Chemistry and Pharmacognosy, Ohio State University College of Pharmacy, 642 Riffe Building, Columbus, OH 43210, USA
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54
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Zhang P, Ma L, Yang Z, Li H, Gao Z. Study on the detoxification mechanisms to 5,10,15,20-tetrakis (4-sulfonatophenyl) porphyrinato iron(III) chloride (FeTPPS), an efficient pro-oxidant of heme water-soluble analogue. J Inorg Biochem 2018; 189:40-52. [DOI: 10.1016/j.jinorgbio.2018.08.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 08/19/2018] [Accepted: 08/30/2018] [Indexed: 11/30/2022]
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Forsyth VT, Moody P. Neutron scattering for the study of biological systems - major opportunities within a rapidly changing landscape. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2018; 74:1126-1128. [PMID: 30605129 DOI: 10.1107/s2059798318017886] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- V Trevor Forsyth
- Partnership for Structural Biology, Institut Laue-Langevin, 6 rue Jules Horowitz, 38042 Grenoble CEDEX 9 France
| | - Peter Moody
- Henry Wellcome Laboratories for Structural Biology, Leicester Institute for Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 7RH, UK
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56
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Adam SM, Wijeratne GB, Rogler PJ, Diaz DE, Quist DA, Liu JJ, Karlin KD. Synthetic Fe/Cu Complexes: Toward Understanding Heme-Copper Oxidase Structure and Function. Chem Rev 2018; 118:10840-11022. [PMID: 30372042 PMCID: PMC6360144 DOI: 10.1021/acs.chemrev.8b00074] [Citation(s) in RCA: 145] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Heme-copper oxidases (HCOs) are terminal enzymes on the mitochondrial or bacterial respiratory electron transport chain, which utilize a unique heterobinuclear active site to catalyze the 4H+/4e- reduction of dioxygen to water. This process involves a proton-coupled electron transfer (PCET) from a tyrosine (phenolic) residue and additional redox events coupled to transmembrane proton pumping and ATP synthesis. Given that HCOs are large, complex, membrane-bound enzymes, bioinspired synthetic model chemistry is a promising approach to better understand heme-Cu-mediated dioxygen reduction, including the details of proton and electron movements. This review encompasses important aspects of heme-O2 and copper-O2 (bio)chemistries as they relate to the design and interpretation of small molecule model systems and provides perspectives from fundamental coordination chemistry, which can be applied to the understanding of HCO activity. We focus on recent advancements from studies of heme-Cu models, evaluating experimental and computational results, which highlight important fundamental structure-function relationships. Finally, we provide an outlook for future potential contributions from synthetic inorganic chemistry and discuss their implications with relevance to biological O2-reduction.
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Affiliation(s)
- Suzanne M. Adam
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Gayan B. Wijeratne
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Patrick J. Rogler
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Daniel E. Diaz
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - David A. Quist
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Jeffrey J. Liu
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kenneth D. Karlin
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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57
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Sullivan B, Archibald R, Langan PS, Dobbek H, Bommer M, McFeeters RL, Coates L, Wang X, Gallmeier F, Carpenter JM, Lynch V, Langan P. Improving the accuracy and resolution of neutron crystallographic data by three-dimensional profile fitting of Bragg peaks in reciprocal space. Acta Crystallogr D Struct Biol 2018; 74:1085-1095. [PMID: 30387767 PMCID: PMC6213576 DOI: 10.1107/s2059798318013347] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 09/18/2018] [Indexed: 11/29/2022] Open
Abstract
Neutron crystallography is a powerful technique for directly visualizing the locations of H atoms in biological macromolecules. This information has provided key new insights into enzyme mechanisms, ligand binding and hydration. However, despite the importance of this information, the application of neutron crystallography in biology has been limited by the relatively low flux of available neutron beams and the large incoherent neutron scattering from hydrogen, both of which contribute to weak diffraction data with relatively low signal-to-background ratios. A method has been developed to fit weak data based on three-dimensional profile fitting of Bragg peaks in reciprocal space by an Ikeda-Carpenter function with a bivariate Gaussian. When applied to data collected from three different proteins, three-dimensional profile fitting yields intensities with higher correlation coefficients (CC1/2) at high resolutions, decreased Rfree factors, extended resolutions and improved nuclear density maps. Importantly, additional features are revealed in nuclear density maps that may provide additional scientific information. These results suggest that three-dimensional profile fitting will help to extend the capabilities of neutron macromolecular crystallography.
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Affiliation(s)
- Brendan Sullivan
- Neutron Scattering Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Rick Archibald
- Computer Science and Mathematics Division, Computing and Computational Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Patricia S. Langan
- Neutron Scattering Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Holger Dobbek
- Institut für Biologie, Humboldt-Universität zu Berlin, Philippstrasse 13, Leonor Michaelis Haus, 10115 Berlin, Germany
| | - Martin Bommer
- Institut für Biologie, Humboldt-Universität zu Berlin, Philippstrasse 13, Leonor Michaelis Haus, 10115 Berlin, Germany
| | - Robert L. McFeeters
- Department of Chemistry, University of Alabama in Huntsville, 301 Sparkman Drive, Huntsville, AL 35899, USA
| | - Leighton Coates
- Neutron Scattering Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Xiaoping Wang
- Neutron Scattering Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Franz Gallmeier
- Neutron Technologies Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - John M. Carpenter
- Neutron Technologies Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Vickie Lynch
- Neutron Scattering Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Paul Langan
- Neutron Scattering Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
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58
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Andris E, Navrátil R, Jašík J, Puri M, Costas M, Que L, Roithová J. Trapping Iron(III)-Oxo Species at the Boundary of the "Oxo Wall": Insights into the Nature of the Fe(III)-O Bond. J Am Chem Soc 2018; 140:14391-14400. [PMID: 30336001 DOI: 10.1021/jacs.8b08950] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Terminal non-heme iron(IV)-oxo compounds are among the most powerful and best studied oxidants of strong C-H bonds. In contrast to the increasing number of such complexes (>80 thus far), corresponding one-electron-reduced derivatives are much rarer and presumably less stable, and only two iron(III)-oxo complexes have been characterized to date, both of which are stabilized by hydrogen-bonding interactions. Herein we have employed gas-phase techniques to generate and identify a series of terminal iron(III)-oxo complexes, all without built-in hydrogen bonding. Some of these complexes exhibit ∼70 cm-1 decrease in ν(Fe-O) frequencies expected for a half-order decrease in bond order upon one-electron reduction to an S = 5/2 center, while others have ν(Fe-O) frequencies essentially unchanged from those of their parent iron(IV)-oxo complexes. The latter result suggests that the added electron does not occupy a d orbital with Fe═O antibonding character, requiring an S = 3/2 spin assignment for the nascent FeIII-O- species. In the latter cases, water is found to hydrogen bond to the FeIII-O- unit, resulting in a change from quartet to sextet spin state. Reactivity studies also demonstrate the extraordinary basicity of these iron(III)-oxo complexes. Our observations show that metal-oxo species at the boundary of the "Oxo Wall" are accessible, and the data provide a lead to detect iron(III)-oxo intermediates in biological and biomimetic reactions.
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Affiliation(s)
- Erik Andris
- Department of Organic Chemistry, Faculty of Science , Charles University , Hlavova 2030/8 , 128 43 Prague 2 , Czech Republic
| | - Rafael Navrátil
- Department of Organic Chemistry, Faculty of Science , Charles University , Hlavova 2030/8 , 128 43 Prague 2 , Czech Republic
| | - Juraj Jašík
- Department of Organic Chemistry, Faculty of Science , Charles University , Hlavova 2030/8 , 128 43 Prague 2 , Czech Republic
| | - Mayank Puri
- Department of Chemistry and Center for Metals in Biocatalysis , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Miquel Costas
- Departament de Quimica and Institute of Computational Chemistry and Catalysis (IQCC) , University of Girona , Campus Montilivi , Girona 17071 , Spain
| | - Lawrence Que
- Department of Chemistry and Center for Metals in Biocatalysis , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Jana Roithová
- Department of Organic Chemistry, Faculty of Science , Charles University , Hlavova 2030/8 , 128 43 Prague 2 , Czech Republic.,Institute for Molecules and Materials , Radboud University , Heyendaalseweg 135 , 6525 AJ Nijmegen , Netherlands
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59
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Harp JM, Coates L, Sullivan B, Egli M. Cryo-neutron crystallographic data collection and preliminary refinement of left-handed Z-DNA d(CGCGCG). Acta Crystallogr F Struct Biol Commun 2018; 74:603-609. [PMID: 30279310 PMCID: PMC6168769 DOI: 10.1107/s2053230x1801066x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 07/24/2018] [Indexed: 11/10/2022] Open
Abstract
Crystals of left-handed Z-DNA [d(CGCGCG)]2 diffract X-rays to beyond 1 Å resolution, feature a small unit cell (∼18 × 31 × 44 Å) and are well hydrated, with around 90 water molecules surrounding the duplex in the asymmetric unit. The duplex shows regular hydration patterns in the narrow minor groove, on the convex surface and around sugar-phosphate backbones. Therefore, Z-DNA offers an ideal case to test the benefits of low-temperature neutron diffraction data collection to potentially determine the donor-acceptor patterns of first- and second-shell water molecules. Nucleic acid fragments pose challenges for neutron crystallography because water molecules are located on the surface rather than inside sequestered spaces such as protein active sites or channels. Water molecules can be expected to display dynamic behavior, particularly in cases where water is not part of an inner shell and directly coordinated to DNA atoms. Thus, nuclear density maps based on room-temperature diffraction data with a resolution of 1.6 Å did not allow an unequivocal determination of the orientations of water molecules. Here, cryo-neutron diffraction data collection for a Z-DNA crystal on the Macromolecular Neutron Diffractometer at the Spallation Neutron Source at Oak Ridge National Laboratory and the outcome of an initial refinement of the structure are reported. A total of 12 diffraction images were recorded with an exposure time of 3.5 h per image, whereby the crystal was static for each diffraction image with a 10° ϕ rotation between images. Initial refinements using these neutron data indicated the positions and orientations of 30 water molecules within the first hydration shell of the DNA molecule. This experiment constitutes a state-of-the-art approach and is the first attempt to our knowledge to determine the low-temperature neutron structure of a DNA crystal.
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Affiliation(s)
- Joel M. Harp
- Department of Biochemistry and Center for Structural Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Leighton Coates
- Neutron Scattering Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Brendan Sullivan
- Neutron Scattering Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Martin Egli
- Department of Biochemistry and Center for Structural Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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60
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Azadmanesh J, Lutz WE, Weiss KL, Coates L, Borgstahl GEO. Redox manipulation of the manganese metal in human manganese superoxide dismutase for neutron diffraction. Acta Crystallogr F Struct Biol Commun 2018; 74:677-687. [PMID: 30279321 PMCID: PMC6168772 DOI: 10.1107/s2053230x18011299] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 08/07/2018] [Indexed: 11/17/2022] Open
Abstract
Human manganese superoxide dismutase (MnSOD) is one of the most significant enzymes in preventing mitochondrial dysfunction and related diseases by combating reactive oxygen species (ROS) in the mitochondrial matrix. Mitochondria are the source of up to 90% of cellular ROS generation, and MnSOD performs its necessary bioprotective role by converting superoxide into oxygen and hydrogen peroxide. This vital catalytic function is conducted via cyclic redox reactions between the substrate and the active-site manganese using proton-coupled electron transfers. Owing to protons being difficult to detect experimentally, the series of proton transfers that compose the catalytic mechanism of MnSOD are unknown. Here, methods are described to discern the proton-based mechanism using chemical treatments to control the redox state of large perdeuterated MnSOD crystals and subsequent neutron diffraction. These methods could be applicable to other crystal systems in which proton information on the molecule in question in specific chemical states is desired.
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Affiliation(s)
- Jahaun Azadmanesh
- Eppley Institute for Research in Cancer and Allied Diseases, 986805 Nebraska Medical Center, Omaha, NE 68198-6805, USA
- Department of Biochemistry and Molecular Biology, 985870 Nebraska Medical Center, Omaha, NE 68198-5870, USA
| | - William E. Lutz
- Eppley Institute for Research in Cancer and Allied Diseases, 986805 Nebraska Medical Center, Omaha, NE 68198-6805, USA
| | - Kevin L. Weiss
- Biology and Soft Matter Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Leighton Coates
- Biology and Soft Matter Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831, USA
| | - Gloria E. O. Borgstahl
- Eppley Institute for Research in Cancer and Allied Diseases, 986805 Nebraska Medical Center, Omaha, NE 68198-6805, USA
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61
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Weber DS, Warren JJ. A survey of methionine-aromatic interaction geometries in the oxidoreductase class of enzymes: What could Met-aromatic interactions be doing near metal sites? J Inorg Biochem 2018; 186:34-41. [DOI: 10.1016/j.jinorgbio.2018.05.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 04/27/2018] [Accepted: 05/16/2018] [Indexed: 10/16/2022]
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62
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Tanaka I, Komatsuzaki N, Yue WX, Chatake T, Kusaka K, Niimura N, Miura D, Iwata T, Miyachi Y, Nukazuka G, Matsuda H. Cryoprotectant-free high-pressure cooling and dynamic nuclear polarization for more sensitive detection of hydrogen in neutron protein crystallography. Acta Crystallogr D Struct Biol 2018; 74:787-791. [PMID: 30082514 PMCID: PMC6079630 DOI: 10.1107/s2059798318005028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 03/27/2018] [Indexed: 11/21/2022] Open
Abstract
To improve the sensitivity of hydrogen detection using neutrons, a proton-polarization technique together with a high-pressure cooling method is necessary. The highest pressure (200 MPa) used in the experiment described here enabled relatively large protein crystals to be cooled without any cryoprotectants while retaining the protein structure, and it was confirmed that high-pressure-cooled crystals diffracted to nearly the same resolution as flash-cooled small crystals soaked with cryoprotectants. Dynamic nuclear polarization was used as a proton-polarization technique for protein crystals, and ∼300 mg polycrystalline protein doped with TEMPOL gave a maximum proton polarization of 22.3% at a temperature of 0.5 K in a 2.5 T magnetic field.
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Affiliation(s)
- Ichiro Tanaka
- College of Engineering, Ibaraki University, Hitachi, Ibaraki 316-8511, Japan
- Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai, Ibaraki 319-1106, Japan
| | - Naoya Komatsuzaki
- Graduate School of Science and Engineering, Ibaraki University, Hitachi, Ibaraki 316-8511, Japan
| | - Wen-Xue Yue
- Graduate School of Science and Engineering, Ibaraki University, Hitachi, Ibaraki 316-8511, Japan
| | - Toshiyuki Chatake
- Research Reactor Institute, Kyoto University, Kumatori, Osaka 590-0494, Japan
| | - Katsuhiro Kusaka
- Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai, Ibaraki 319-1106, Japan
| | - Nobuo Niimura
- Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai, Ibaraki 319-1106, Japan
| | - Daisuke Miura
- Faculty of Science, Yamagata University, Yamagata, Yamagata 990-8560, Japan
| | - Takahiro Iwata
- Faculty of Science, Yamagata University, Yamagata, Yamagata 990-8560, Japan
| | - Yoshiyuki Miyachi
- Faculty of Science, Yamagata University, Yamagata, Yamagata 990-8560, Japan
| | - Genki Nukazuka
- Faculty of Science, Yamagata University, Yamagata, Yamagata 990-8560, Japan
| | - Hiroki Matsuda
- Faculty of Science, Yamagata University, Yamagata, Yamagata 990-8560, Japan
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63
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Kwon H, Langan PS, Coates L, Raven EL, Moody PCE. The rise of neutron cryo-crystallography. Acta Crystallogr D Struct Biol 2018; 74:792-799. [PMID: 30082515 PMCID: PMC6079629 DOI: 10.1107/s205979831800640x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 04/25/2018] [Indexed: 11/10/2022] Open
Abstract
The use of boiled-off liquid nitrogen to maintain protein crystals at 100 K during X-ray data collection has become almost universal. Applying this to neutron protein crystallography offers the opportunity to significantly broaden the scope of biochemical problems that can be addressed, although care must be taken in assuming that direct extrapolation to room temperature is always valid. Here, the history to date of neutron protein cryo-crystallography and the particular problems and solutions associated with the mounting and cryocooling of the larger crystals needed for neutron crystallography are reviewed. Finally, the outlook for further cryogenic neutron studies using existing and future neutron instrumentation is discussed.
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Affiliation(s)
- Hanna Kwon
- Henry Wellcome Laboratories for Structural Biology, Leicester Institute of Structural and Chemical Biology, Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 7RH, England
| | - Patricia S. Langan
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Leighton Coates
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Emma L. Raven
- Leicester Institute of Structural and Chemical Biology, Department of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, England
| | - Peter C. E. Moody
- Henry Wellcome Laboratories for Structural Biology, Leicester Institute of Structural and Chemical Biology, Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 7RH, England
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64
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Liebschner D, Afonine PV, Moriarty NW, Langan P, Adams PD. Evaluation of models determined by neutron diffraction and proposed improvements to their validation and deposition. Acta Crystallogr D Struct Biol 2018; 74:800-813. [PMID: 30082516 PMCID: PMC6079631 DOI: 10.1107/s2059798318004588] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 03/19/2018] [Indexed: 11/10/2022] Open
Abstract
The Protein Data Bank (PDB) contains a growing number of models that have been determined using neutron diffraction or a hybrid method that combines X-ray and neutron diffraction. The advantage of neutron diffraction experiments is that the positions of all atoms can be determined, including H atoms, which are hardly detectable by X-ray diffraction. This allows the determination of protonation states and the assignment of H atoms to water molecules. Because neutrons are scattered differently by hydrogen and its isotope deuterium, neutron diffraction in combination with H/D exchange can provide information on accessibility, dynamics and chemical lability. In this study, the deposited data, models and model-to-data fit for all PDB entries that used neutron diffraction as the source of experimental data have been analysed. In many cases, the reported Rwork and Rfree values were not reproducible. In such cases, the model and data files were analysed to identify the reasons for this mismatch. The issues responsible for the discrepancies are summarized and explained. The analysis unveiled limitations to the annotation, deposition and validation of models and data, and a lack of community-wide accepted standards for the description of neutron models and data, as well as deficiencies in current model refinement tools. Most of the issues identified concern the handling of H atoms. Since the primary use of neutron macromolecular crystallography is to locate and directly visualize H atoms, it is important to address these issues, so that the deposited neutron models allow the retrieval of the maximum amount of information with the smallest effort of manual intervention. A path forward to improving the annotation, validation and deposition of neutron models and hybrid X-ray and neutron models is suggested.
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Affiliation(s)
- Dorothee Liebschner
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Pavel V. Afonine
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Physics and International Centre for Quantum and Molecular Structures, Shanghai University, Shanghai 200444, People’s Republic of China
| | - Nigel W. Moriarty
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Paul Langan
- Neutron Science Directorate, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831, USA
| | - Paul D. Adams
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Bioengineering, University of California, Berkeley, CA 94720, USA
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65
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Schröder GC, O'Dell WB, Myles DAA, Kovalevsky A, Meilleur F. IMAGINE: neutrons reveal enzyme chemistry. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2018; 74:778-786. [DOI: 10.1107/s2059798318001626] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 01/26/2018] [Indexed: 11/10/2022]
Abstract
Neutron diffraction is exquisitely sensitive to the positions of H atoms in protein crystal structures. IMAGINE is a high-intensity, quasi-Laue neutron crystallography beamline developed at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory. This state-of-the-art facility for neutron diffraction has enabled detailed structural analysis of macromolecules. IMAGINE is especially suited to resolve individual H atoms in protein structures, enabling neutron protein structures to be determined at or near atomic resolutions from crystals with volumes of less than 1 mm3 and unit-cell edges of less than 150 Å. Beamline features include elliptical focusing mirrors that deliver neutrons into a 2.0 × 3.2 mm focal spot at the sample position, and variable short- and long-wavelength cutoff optics that provide automated exchange between multiple wavelength configurations. This review gives an overview of the IMAGINE beamline at the HFIR, presents examples of the scientific questions being addressed at this beamline, and highlights important findings in enzyme chemistry that have been made using the neutron diffraction capabilities offered by IMAGINE.
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66
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Pankhurst JR, Curcio M, Sproules S, Lloyd-Jones GC, Love JB. Earth-Abundant Mixed-Metal Catalysts for Hydrocarbon Oxygenation. Inorg Chem 2018; 57:5915-5928. [DOI: 10.1021/acs.inorgchem.8b00420] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- James R. Pankhurst
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, U.K
| | - Massimiliano Curcio
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, U.K
| | - Stephen Sproules
- WestCHEM School of Chemistry, University of Glasgow, Glasgow G12 8QQ, U.K
| | - Guy C. Lloyd-Jones
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, U.K
| | - Jason B. Love
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, U.K
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67
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Amaro RE, Mulholland AJ. Multiscale Methods in Drug Design Bridge Chemical and Biological Complexity in the Search for Cures. Nat Rev Chem 2018; 2:0148. [PMID: 30949587 PMCID: PMC6445369 DOI: 10.1038/s41570-018-0148] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Drug action is inherently multiscale: it connects molecular interactions to emergent properties at cellular and larger scales. Simulation techniques at each of these different scales are already central to drug design and development, but methods capable of connecting across these scales will extend understanding of complex mechanisms and the ability to predict biological effects. Improved algorithms, ever-more-powerful computing architectures and the accelerating growth of rich datasets are driving advances in multiscale modeling methods capable of bridging chemical and biological complexity from the atom to the cell. Particularly exciting is the development of highly detailed, structure-based, physical simulations of biochemical systems, which are now able to access experimentally relevant timescales for large systems and, at the same time, achieve unprecedented accuracy. In this Perspective, we discuss how emerging data-rich, physics-based multiscale approaches are of the cusp of realizing long-promised impact in the discovery, design and development of novel therapeutics. We highlight emerging methods and applications in this growing field, and outline how different scales can be combined in practical modelling and simulation strategies.
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Affiliation(s)
- Rommie E Amaro
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0304
| | - Adrian J Mulholland
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS, UK
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68
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Huang X, Groves JT. Oxygen Activation and Radical Transformations in Heme Proteins and Metalloporphyrins. Chem Rev 2018; 118:2491-2553. [PMID: 29286645 PMCID: PMC5855008 DOI: 10.1021/acs.chemrev.7b00373] [Citation(s) in RCA: 591] [Impact Index Per Article: 98.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Indexed: 12/20/2022]
Abstract
As a result of the adaptation of life to an aerobic environment, nature has evolved a panoply of metalloproteins for oxidative metabolism and protection against reactive oxygen species. Despite the diverse structures and functions of these proteins, they share common mechanistic grounds. An open-shell transition metal like iron or copper is employed to interact with O2 and its derived intermediates such as hydrogen peroxide to afford a variety of metal-oxygen intermediates. These reactive intermediates, including metal-superoxo, -(hydro)peroxo, and high-valent metal-oxo species, are the basis for the various biological functions of O2-utilizing metalloproteins. Collectively, these processes are called oxygen activation. Much of our understanding of the reactivity of these reactive intermediates has come from the study of heme-containing proteins and related metalloporphyrin compounds. These studies not only have deepened our understanding of various functions of heme proteins, such as O2 storage and transport, degradation of reactive oxygen species, redox signaling, and biological oxygenation, etc., but also have driven the development of bioinorganic chemistry and biomimetic catalysis. In this review, we survey the range of O2 activation processes mediated by heme proteins and model compounds with a focus on recent progress in the characterization and reactivity of important iron-oxygen intermediates. Representative reactions initiated by these reactive intermediates as well as some context from prior decades will also be presented. We will discuss the fundamental mechanistic features of these transformations and delineate the underlying structural and electronic factors that contribute to the spectrum of reactivities that has been observed in nature as well as those that have been invented using these paradigms. Given the recent developments in biocatalysis for non-natural chemistries and the renaissance of radical chemistry in organic synthesis, we envision that new enzymatic and synthetic transformations will emerge based on the radical processes mediated by metalloproteins and their synthetic analogs.
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Affiliation(s)
- Xiongyi Huang
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
- Department
of Chemistry, California Institute of Technology, Pasadena, California 91125, United States
| | - John T. Groves
- Department
of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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69
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Abstract
Aerobic organisms have evolved to activate oxygen from the atmosphere, which allows them to catalyze the oxidation of different kinds of substrates. This activation of oxygen is achieved by a metal center (usually iron or copper) buried within a metalloprotein. In the case of iron-containing heme enzymes, the activation of oxygen is achieved by formation of transient iron-oxo (ferryl) intermediates; these intermediates are called Compound I and Compound II. The Compound I and II intermediates were first discovered in the 1930s in horseradish peroxidase, and it is now known that these same species are used across the family of heme enzymes, which include all of the peroxidases, the heme catalases, the P450s, cytochrome c oxidase, and NO synthase. Many years have passed since the first observations, but establishing the chemical nature of these transient ferryl species remains a fundamental question that is relevant to the reactivity, and therefore the usefulness, of these species in biology. This Account summarizes experiments that were conceived and conducted at Leicester and presents our ideas on the chemical nature, stability, and reactivity of these ferryl heme species. We begin by briefly summarizing the early milestones in the field, from the 1940s and 1950s. We present comparisons between the nature and reactivity of the ferryl species in horseradish peroxidase, cytochrome c peroxidase, and ascorbate peroxidase; and we consider different modes of electron delivery to ferryl heme, from different substrates in different peroxidases. We address the question of whether the ferryl heme is best formulated as an (unprotonated) FeIV═O or as a (protonated) FeIV-OH species. A range of spectroscopic approaches (EXAFS, resonance Raman, Mossbauer, and EPR) have been used over many decades to examine this question, and in the last ten years, X-ray crystallography has also been employed. We describe how information from all of these studies has blended together to create an overall picture, and how the recent application of neutron crystallography has directly identified protonation states and has helped to clarify the precise nature of the ferryl heme in cytochrome c peroxidase and ascorbate peroxidase. We draw comparisons between the Compound I and Compound II species that we have observed in peroxidases with those found in other heme systems, notably the P450s, highlighting possible commonality across these heme ferryl systems. The identification of proton locations from neutron structures of these ferryl species opens the door for understanding the proton translocations that need to occur during O-O bond cleavage.
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Affiliation(s)
- Peter C. E. Moody
- Department
of Molecular and Cell Biology and Leicester Institute of Structural
and Chemical Biology, University of Leicester, Lancaster Road, Leicester LE1 9HN, England
| | - Emma L. Raven
- Department
of Chemistry and Leicester Institute of Structural and Chemical Biology, University of Leicester, University Road, Leicester LE1 7RH, U.K
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70
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Neutron macromolecular crystallography. Emerg Top Life Sci 2018; 2:39-55. [DOI: 10.1042/etls20170083] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 12/12/2017] [Accepted: 12/19/2017] [Indexed: 01/02/2023]
Abstract
Neutron diffraction techniques permit direct determination of the hydrogen (H) and deuterium (D) positions in crystal structures of biological macromolecules at resolutions of ∼1.5 and 2.5 Å, respectively. In addition, neutron diffraction data can be collected from a single crystal at room temperature without radiation damage issues. By locating the positions of H/D-atoms, protonation states and water molecule orientations can be determined, leading to a more complete understanding of many biological processes and drug-binding. In the last ca. 5 years, new beamlines have come online at reactor neutron sources, such as BIODIFF at Heinz Maier-Leibnitz Zentrum and IMAGINE at Oak Ridge National Laboratory (ORNL), and at spallation neutron sources, such as MaNDi at ORNL and iBIX at the Japan Proton Accelerator Research Complex. In addition, significant improvements have been made to existing beamlines, such as LADI-III at the Institut Laue-Langevin. The new and improved instrumentations are allowing sub-mm3 crystals to be regularly used for data collection and permitting the study of larger systems (unit-cell edges >100 Å). Owing to this increase in capacity and capability, many more studies have been performed and for a wider range of macromolecules, including enzymes, signalling proteins, transport proteins, sugar-binding proteins, fluorescent proteins, hormones and oligonucleotides; of the 126 structures deposited in the Protein Data Bank, more than half have been released since 2013 (65/126, 52%). Although the overall number is still relatively small, there are a growing number of examples for which neutron macromolecular crystallography has provided the answers to questions that otherwise remained elusive.
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71
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Moulin M, Strohmeier GA, Hirz M, Thompson KC, Rennie AR, Campbell RA, Pichler H, Maric S, Forsyth VT, Haertlein M. Perdeuteration of cholesterol for neutron scattering applications using recombinant Pichia pastoris. Chem Phys Lipids 2018; 212:80-87. [PMID: 29357283 DOI: 10.1016/j.chemphyslip.2018.01.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 12/20/2017] [Accepted: 01/15/2018] [Indexed: 02/08/2023]
Abstract
Deuteration of biomolecules has a major impact on both quality and scope of neutron scattering experiments. Cholesterol is a major component of mammalian cells, where it plays a critical role in membrane permeability, rigidity and dynamics, and contributes to specific membrane structures such as lipid rafts. Cholesterol is the main cargo in low and high-density lipoprotein complexes (i.e. LDL, HDL) and is directly implicated in several pathogenic conditions such as coronary artery disease which leads to 17 million deaths annually. Neutron scattering studies on membranes or lipid-protein complexes exploiting contrast variation have been limited by the lack of availability of fully deuterated biomolecules and especially perdeuterated cholesterol. The availability of perdeuterated cholesterol provides a unique way of probing the structural and dynamical properties of the lipoprotein complexes that underly many of these disease conditions. Here we describe a procedure for in vivo production of perdeuterated recombinant cholesterol in lipid-engineered Pichia pastoris using flask and fed-batch fermenter cultures in deuterated minimal medium. Perdeuteration of the purified cholesterol was verified by mass spectrometry and its use in a neutron scattering study was demonstrated by neutron reflectometry measurements using the FIGARO instrument at the ILL.
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Affiliation(s)
- Martine Moulin
- Institut Laue-Langevin, 71, Avenue des Martyrs, Grenoble 38042, France; Faculty of Natural Sciences, Keele University, Keele, Staffordshire ST5 5BG, United Kingdom
| | - Gernot A Strohmeier
- acib, Austrian Centre of Industrial Biotechnology GmbH, 8010 Graz, Austria; Institute of Organic Chemistry, NAWI Graz, Graz University of Technology, 8010 Graz, Austria
| | - Melanie Hirz
- Institute of Molecular Biotechnology, NAWI Graz, BioTechMed Graz, Graz University of Technology, 8010 Graz, Austria
| | - Katherine C Thompson
- Department of Biological Sciences and Institute of Structural and Molecular Biology, Birkbeck College, University of London, Malet Street, London WC1E 7HX, United Kingdom
| | - Adrian R Rennie
- Centre for Neutron Scattering, Uppsala University, 751 20 Uppsala, Sweden
| | | | - Harald Pichler
- acib, Austrian Centre of Industrial Biotechnology GmbH, 8010 Graz, Austria; Institute of Molecular Biotechnology, NAWI Graz, BioTechMed Graz, Graz University of Technology, 8010 Graz, Austria
| | - Selma Maric
- Biofilms - Research Centre for Biointerfaces and Biomedical Science Department, Faculty of Health and Society, Malmö University, Malmö 20506, Sweden
| | - V Trevor Forsyth
- Institut Laue-Langevin, 71, Avenue des Martyrs, Grenoble 38042, France; Faculty of Natural Sciences, Keele University, Keele, Staffordshire ST5 5BG, United Kingdom
| | - Michael Haertlein
- Institut Laue-Langevin, 71, Avenue des Martyrs, Grenoble 38042, France.
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72
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Construction and in vivo assembly of a catalytically proficient and hyperthermostable de novo enzyme. Nat Commun 2017; 8:358. [PMID: 28842561 PMCID: PMC5572459 DOI: 10.1038/s41467-017-00541-4] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 07/07/2017] [Indexed: 11/08/2022] Open
Abstract
Although catalytic mechanisms in natural enzymes are well understood, achieving the diverse palette of reaction chemistries in re-engineered native proteins has proved challenging. Wholesale modification of natural enzymes is potentially compromised by their intrinsic complexity, which often obscures the underlying principles governing biocatalytic efficiency. The maquette approach can circumvent this complexity by combining a robust de novo designed chassis with a design process that avoids atomistic mimicry of natural proteins. Here, we apply this method to the construction of a highly efficient, promiscuous, and thermostable artificial enzyme that catalyzes a diverse array of substrate oxidations coupled to the reduction of H2O2. The maquette exhibits kinetics that match and even surpass those of certain natural peroxidases, retains its activity at elevated temperature and in the presence of organic solvents, and provides a simple platform for interrogating catalytic intermediates common to natural heme-containing enzymes.Catalytic mechanisms of enzymes are well understood, but achieving diverse reaction chemistries in re-engineered proteins can be difficult. Here the authors show a highly efficient and thermostable artificial enzyme that catalyzes a diverse array of substrate oxidations coupled to the reduction of H2O2.
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73
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Unconventional N-H…N Hydrogen Bonds Involving Proline Backbone Nitrogen in Protein Structures. Biophys J 2017; 110:1967-79. [PMID: 27166805 DOI: 10.1016/j.bpj.2016.03.034] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 03/28/2016] [Accepted: 03/29/2016] [Indexed: 01/08/2023] Open
Abstract
Contrary to DNA double-helical structures, hydrogen bonds (H-bonds) involving nitrogen as the acceptor are not common in protein structures. We systematically searched N-H…N H-bonds in two different sets of protein structures. Data set I consists of neutron diffraction and ultrahigh-resolution x-ray structures (0.9 Å resolution or better) and the hydrogen atom positions in these structures were determined experimentally. Data set II contains structures determined using x-ray diffraction (resolution ≤ 1.8 Å) and the positions of hydrogen atoms were generated using a computational method. We identified 114 and 14,347 potential N-H…N H-bonds from these two data sets, respectively, and 56-66% of these were of the Ni+1-Hi+1…Ni type, with Ni being the proline backbone nitrogen. To further understand the nature of such unusual contacts, we performed quantum chemical calculations on the model compound N-acetyl-L-proline-N-methylamide (Ace-Pro-NMe) with coordinates taken from the experimentally determined structures. A potential energy profile generated by varying the ψ dihedral angle in Ace-Pro-NMe indicates that the conformation with the N-H…N H-bond is the most stable. An analysis of H-bond-forming proline residues reveals that more than 30% of the proline carbonyl groups are also involved in n → π(∗) interactions with the carbonyl carbon of the preceding residue. Natural bond orbital analyses demonstrate that the strength of N-H…N H-bonds is less than half of that observed for a conventional H-bond. This study clearly establishes the H-bonding capability of proline nitrogen and its prevalence in protein structures. We found many proteins with multiple instances of H-bond-forming prolines. With more than 15% of all proline residues participating in N-H…N H-bonds, we suggest a new, to our knowledge, structural role for proline in providing stability to loops and capping regions of secondary structures in proteins.
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74
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Roy S, Kästner J. Catalytic Mechanism of Salicylate Dioxygenase: QM/MM Simulations Reveal the Origin of Unexpected Regioselectivity of the Ring Cleavage. Chemistry 2017; 23:8949-8962. [DOI: 10.1002/chem.201701286] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Subhendu Roy
- Institute for Theoretical Chemistry; University of Stuttgart; Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Johannes Kästner
- Institute for Theoretical Chemistry; University of Stuttgart; Pfaffenwaldring 55 70569 Stuttgart Germany
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75
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Oksanen E, Chen JCH, Fisher SZ. Neutron Crystallography for the Study of Hydrogen Bonds in Macromolecules. Molecules 2017; 22:molecules22040596. [PMID: 28387738 PMCID: PMC6154725 DOI: 10.3390/molecules22040596] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Revised: 03/29/2017] [Accepted: 04/01/2017] [Indexed: 11/21/2022] Open
Abstract
The hydrogen bond (H bond) is one of the most important interactions that form the foundation of secondary and tertiary protein structure. Beyond holding protein structures together, H bonds are also intimately involved in solvent coordination, ligand binding, and enzyme catalysis. The H bond by definition involves the light atom, H, and it is very difficult to study directly, especially with X-ray crystallographic techniques, due to the poor scattering power of H atoms. Neutron protein crystallography provides a powerful, complementary tool that can give unambiguous information to structural biologists on solvent organization and coordination, the electrostatics of ligand binding, the protonation states of amino acid side chains and catalytic water species. The method is complementary to X-ray crystallography and the dynamic data obtainable with NMR spectroscopy. Also, as it gives explicit H atom positions, it can be very valuable to computational chemistry where exact knowledge of protonation and solvent orientation can make a large difference in modeling. This article gives general information about neutron crystallography and shows specific examples of how the method has contributed to structural biology, structure-based drug design; and the understanding of fundamental questions of reaction mechanisms.
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Affiliation(s)
- Esko Oksanen
- Science Directorate, European Spallation Source ERIC, Tunavägen 24, 22100 Lund, Sweden.
- Department of Biochemistry and Structural Biology, Lund University, Sölvegatan 39, 22362 Lund, Sweden.
| | - Julian C-H Chen
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
| | - Suzanne Zoë Fisher
- Science Directorate, European Spallation Source ERIC, Tunavägen 24, 22100 Lund, Sweden.
- Department of Biology, Lund University, Sölvegatan 35, 22362 Lund, Sweden.
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76
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Yosca TH, Ledray AP, Ngo J, Green MT. A new look at the role of thiolate ligation in cytochrome P450. J Biol Inorg Chem 2017; 22:209-220. [PMID: 28091754 PMCID: PMC5640440 DOI: 10.1007/s00775-016-1430-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Accepted: 12/14/2016] [Indexed: 10/20/2022]
Abstract
Protonated ferryl (or iron(IV)hydroxide) intermediates have been characterized in several thiolate-ligated heme proteins that are known to catalyze C-H bond activation. The basicity of the ferryl intermediates in these species has been proposed to play a critical role in facilitating this chemistry, allowing hydrogen abstraction at reduction potentials below those that would otherwise lead to oxidative degradation of the enzyme. In this contribution, we discuss the events that led to the assignment and characterization of the unusual iron(IV)hydroxide species, highlighting experiments that provided a quantitative measure of the ferryl basicity, the iron(IV)hydroxide pKa. We then turn to the importance of the iron(IV)hydroxide state, presenting a new way of looking at the role of thiolate ligation in these systems.
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Affiliation(s)
- Timothy H Yosca
- Departments of Chemistry & Molecular Biology and Biochemistry, University of California-Irvine, 4134, Natural Sciences 1, Irvine, CA 92697, USA
| | - Aaron P Ledray
- Departments of Chemistry & Molecular Biology and Biochemistry, University of California-Irvine, 4134, Natural Sciences 1, Irvine, CA 92697, USA
| | - Joanna Ngo
- Departments of Chemistry & Molecular Biology and Biochemistry, University of California-Irvine, 4134, Natural Sciences 1, Irvine, CA 92697, USA
| | - Michael T Green
- Departments of Chemistry & Molecular Biology and Biochemistry, University of California-Irvine, 4134, Natural Sciences 1, Irvine, CA 92697, USA.
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77
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Yee AW, Blakeley MP, Moulin M, Haertlein M, Mitchell E, Forsyth VT. Back-exchange of deuterium in neutron crystallography: characterization by IR spectroscopy. J Appl Crystallogr 2017; 50:660-664. [PMID: 28381984 PMCID: PMC5377354 DOI: 10.1107/s1600576717003624] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 03/07/2017] [Indexed: 01/02/2023] Open
Abstract
The application of IR spectroscopy to the characterization and quality control of samples used in neutron crystallography is described. While neutron crystallography is a growing field, the limited availability of neutron beamtime means that there may be a delay between crystallogenesis and data collection. Since essentially all neutron crystallographic work is carried out using D2O-based solvent buffers, a particular concern for these experiments is the possibility of H2O back-exchange across reservoir or capillary sealants. This may limit the quality of neutron scattering length density maps and of the associated analysis. Given the expense of central facility beamtime and the effort that goes into the production of suitably sized (usually perdeuterated) crystals, a systematic method of exploiting IR spectroscopy for the analysis of back-exchange phenomena in the reservoirs used for crystal growth is valuable. Examples are given in which the characterization of D2O/H2O back-exchange in transthyretin crystals is described.
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Affiliation(s)
- Ai Woon Yee
- Life Sciences Group, Institut Laue–Langevin, 71 avenue des Martyrs, Grenoble 38042, France
- Faculty of Natural Sciences, Keele University, Keele ST5 5BG, UK
| | - Matthew P. Blakeley
- Large-Scale Structures Group, Institut Laue–Langevin, 71 avenue des Martyrs, Grenoble 38042, France
| | - Martine Moulin
- Life Sciences Group, Institut Laue–Langevin, 71 avenue des Martyrs, Grenoble 38042, France
- Faculty of Natural Sciences, Keele University, Keele ST5 5BG, UK
| | - Michael Haertlein
- Life Sciences Group, Institut Laue–Langevin, 71 avenue des Martyrs, Grenoble 38042, France
| | - Edward Mitchell
- Faculty of Natural Sciences, Keele University, Keele ST5 5BG, UK
- European Synchrotron Research Facility, 71 avenue des Martyrs, Grenoble 38043, France
| | - V. Trevor Forsyth
- Life Sciences Group, Institut Laue–Langevin, 71 avenue des Martyrs, Grenoble 38042, France
- Faculty of Natural Sciences, Keele University, Keele ST5 5BG, UK
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78
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Kwon H, Smith O, Raven EL, Moody PCE. Combining X-ray and neutron crystallography with spectroscopy. Acta Crystallogr D Struct Biol 2017; 73:141-147. [PMID: 28177310 PMCID: PMC5297917 DOI: 10.1107/s2059798316016314] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 10/13/2016] [Indexed: 12/03/2022] Open
Abstract
X-ray protein crystallography has, through the determination of the three-dimensional structures of enzymes and their complexes, been essential to the understanding of biological chemistry. However, as X-rays are scattered by electrons, the technique has difficulty locating the presence and position of H atoms (and cannot locate H+ ions), knowledge of which is often crucially important for the understanding of enzyme mechanism. Furthermore, X-ray irradiation, through photoelectronic effects, will perturb the redox state in the crystal. By using single-crystal spectrophotometry, reactions taking place in the crystal can be monitored, either to trap intermediates or follow photoreduction during X-ray data collection. By using neutron crystallography, the positions of H atoms can be located, as it is the nuclei rather than the electrons that scatter neutrons, and the scattering length is not determined by the atomic number. Combining the two techniques allows much greater insight into both reaction mechanism and X-ray-induced photoreduction.
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Affiliation(s)
- Hanna Kwon
- Henry Wellcome Laboratories for Structural Biology, Leicester Institute for Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 7RH, England
| | - Oliver Smith
- Henry Wellcome Laboratories for Structural Biology, Leicester Institute for Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 7RH, England
| | - Emma Lloyd Raven
- Leicester Institute for Structural and Chemical Biology and Department of Chemistry, University of Leicester, University Road, Leicester LE1 7RH, England
| | - Peter C. E. Moody
- Henry Wellcome Laboratories for Structural Biology, Leicester Institute for Structural and Chemical Biology and Department of Molecular and Cell Biology, University of Leicester, Lancaster Road, Leicester LE1 7RH, England
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79
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Bax B, Chung CW, Edge C. Getting the chemistry right: protonation, tautomers and the importance of H atoms in biological chemistry. Acta Crystallogr D Struct Biol 2017; 73:131-140. [PMID: 28177309 PMCID: PMC5297916 DOI: 10.1107/s2059798316020283] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/21/2016] [Indexed: 11/13/2023] Open
Abstract
There are more H atoms than any other type of atom in an X-ray crystal structure of a protein-ligand complex, but as H atoms only have one electron they diffract X-rays weakly and are `hard to see'. The positions of many H atoms can be inferred by our chemical knowledge, and such H atoms can be added with confidence in `riding positions'. For some chemical groups, however, there is more ambiguity over the possible hydrogen placements, for example hydroxyls and groups that can exist in multiple protonation states or tautomeric forms. This ambiguity is far from rare, since about 25% of drugs have more than one tautomeric form. This paper focuses on the most common, `prototropic', tautomers, which are isomers that readily interconvert by the exchange of an H atom accompanied by the switch of a single and an adjacent double bond. Hydrogen-exchange rates and different protonation states of compounds (e.g. buffers) are also briefly discussed. The difference in heavy (non-H) atom positions between two tautomers can be small, and careful refinement of all possible tautomers may single out the likely bound ligand tautomer. Experimental methods to determine H-atom positions, such as neutron crystallography, are often technically challenging. Therefore, chemical knowledge and computational approaches are frequently used in conjugation with experimental data to deduce the bound tautomer state. Proton movement is a key feature of many enzymatic reactions, so understanding the orchestration of hydrogen/proton motion is of critical importance to biological chemistry. For example, structural studies have suggested that, just as a chemist may use heat, some enzymes use directional movement to protonate specific O atoms on phosphates to catalyse phosphotransferase reactions. To inhibit `wriggly' enzymes that use movement to effect catalysis, it may be advantageous to have inhibitors that can maintain favourable contacts by adopting different tautomers as the enzyme `wriggles'.
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Affiliation(s)
- Ben Bax
- Structural Biology, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, England
- Platform Technology and Science, GlaxoSmithKline, Medicines Research Centre, Gunnels Wood Road, Stevenage SG1 2NY, England
| | - Chun-wa Chung
- Platform Technology and Science, GlaxoSmithKline, Medicines Research Centre, Gunnels Wood Road, Stevenage SG1 2NY, England
| | - Colin Edge
- Platform Technology and Science, GlaxoSmithKline, Medicines Research Centre, Gunnels Wood Road, Stevenage SG1 2NY, England
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80
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Biological Structures. NEUTRON SCATTERING - APPLICATIONS IN BIOLOGY, CHEMISTRY, AND MATERIALS SCIENCE 2017. [DOI: 10.1016/b978-0-12-805324-9.00001-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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81
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Direct visualization of a Fe(IV)-OH intermediate in a heme enzyme. Nat Commun 2016; 7:13445. [PMID: 27897163 PMCID: PMC5141285 DOI: 10.1038/ncomms13445] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 10/05/2016] [Indexed: 11/21/2022] Open
Abstract
Catalytic heme enzymes carry out a wide range of oxidations in biology. They have in common a mechanism that requires formation of highly oxidized ferryl intermediates. It is these ferryl intermediates that provide the catalytic engine to drive the biological activity. Unravelling the nature of the ferryl species is of fundamental and widespread importance. The essential question is whether the ferryl is best described as a Fe(IV)=O or a Fe(IV)–OH species, but previous spectroscopic and X-ray crystallographic studies have not been able to unambiguously differentiate between the two species. Here we use a different approach. We report a neutron crystal structure of the ferryl intermediate in Compound II of a heme peroxidase; the structure allows the protonation states of the ferryl heme to be directly observed. This, together with pre-steady state kinetic analyses, electron paramagnetic resonance spectroscopy and single crystal X-ray fluorescence, identifies a Fe(IV)–OH species as the reactive intermediate. The structure establishes a precedent for the formation of Fe(IV)–OH in a peroxidase. The nature of the ferryl intermediate generated in reactions catalysed by heme-containing enzymes is uncertain, due to the ambiguity of X-ray crystallography data. Here, the authors apply neutron diffraction, kinetics and other spectroscopy to directly observe a protonated ferryl intermediate in a heme peroxidase.
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82
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Shibata T, Kanai Y, Nishimura R, Xu L, Moritaka Y, Suzuki A, Neya S, Nakamura M, Yamamoto Y. Characterization of Ground State Electron Configurations of High-Spin Quintet Ferrous Heme Iron in Deoxy Myoglobin Reconstituted with Trifluoromethyl Group-Substituted Heme Cofactors. Inorg Chem 2016; 55:12128-12136. [DOI: 10.1021/acs.inorgchem.6b01360] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tomokazu Shibata
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Yuki Kanai
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Ryu Nishimura
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Liyang Xu
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Yuki Moritaka
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
| | - Akihiro Suzuki
- Department of Materials Engineering, Nagaoka National College of Technology, Nagaoka 940-8532, Japan
| | - Saburo Neya
- Department of Physical Chemistry, Graduate School of
Pharmaceutical Sciences, Chiba University, Chuoh-Inohana, Chiba 260-8675, Japan
| | - Mikio Nakamura
- Department
of Chemistry, Faculty of Science, Toho University, Funabashi, Chiba 274-8510, Japan
| | - Yasuhiko Yamamoto
- Department of Chemistry, University of Tsukuba, Tsukuba 305-8571, Japan
- Life Science
Center of Tsukuba Advanced Research Alliance, University of Tsukuba, Tsukuba 305-8577, Japan
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83
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Hill EA, Weitz AC, Onderko E, Romero-Rivera A, Guo Y, Swart M, Bominaar EL, Green MT, Hendrich MP, Lacy DC, Borovik AS. Reactivity of an Fe IV-Oxo Complex with Protons and Oxidants. J Am Chem Soc 2016; 138:13143-13146. [PMID: 27647293 PMCID: PMC5110122 DOI: 10.1021/jacs.6b07633] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
High-valent Fe-OH species are often invoked as key intermediates but have only been observed in Compound II of cytochrome P450s. To further address the properties of non-heme FeIV-OH complexes, we demonstrate the reversible protonation of a synthetic FeIV-oxo species containing a tris-urea tripodal ligand. The same protonated FeIV-oxo species can be prepared via oxidation, suggesting that a putative FeV-oxo species was initially generated. Computational, Mössbauer, XAS, and NRVS studies indicate that protonation of the FeIV-oxo complex most likely occurs on the tripodal ligand, which undergoes a structural change that results in the formation of a new intramolecular H-bond with the oxido ligand that aids in stabilizing the protonated adduct. We suggest that similar protonated high-valent Fe-oxo species may occur in the active sites of proteins. This finding further argues for caution when assigning unverified high-valent Fe-OH species to mechanisms.
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Affiliation(s)
- Ethan A. Hill
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, CA 92697
| | - Andrew C. Weitz
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Elizabeth Onderko
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802
| | - Adrian Romero-Rivera
- Institut de Química Computacional i Catàlisi & Dept. Química, Universitat de Girona, 17003, Spain
| | - Yisong Guo
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Marcel Swart
- Institut de Química Computacional i Catàlisi & Dept. Química, Universitat de Girona, 17003, Spain
- ICREA, Pg. Lluís Companys 23, 08010, Barcelona, Spain
| | - Emile L. Bominaar
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Michael T. Green
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, CA 92697
- Department of Chemistry, Pennsylvania State University, University Park, PA 16802
| | | | - David C. Lacy
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, CA 92697
| | - A. S. Borovik
- Department of Chemistry, University of California-Irvine, 1102 Natural Sciences II, Irvine, CA 92697
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84
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Abstract
Since drugs bind to their targets through directional H bonding and non-directional hydrophobic and electrostatic interactions, neutron crystallography can help guide structure-based drug design. This is illustrated by McKenna and co-workers [Aggarwal et al. (2016), IUCrJ, 3, 319-325] who describe the room-temperature neutron structure of human carbonic anyhydrase II in complex with the clinical inhibitor methazolamide to 2.2 Å resolution, and compare this with the previously determined room-temperature neutron structure of human carbonic anyhydrase II in complex with the clinical inhibitor acetazolamide to 2.0 Å resolution [Fisher et al. (2012). J. Am. Chem. Soc.134, 14726-14729].
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Affiliation(s)
- M. P. Blakeley
- Large-Scale Structures Group, Institut Laue-Langevin, 71 Avenue des Martyrs, Grenoble, 38000, France
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85
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Cuypers MG, Mason SA, Mossou E, Haertlein M, Forsyth VT, Mitchell EP. Macromolecular structure phasing by neutron anomalous diffraction. Sci Rep 2016; 6:31487. [PMID: 27511806 PMCID: PMC4980602 DOI: 10.1038/srep31487] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 07/20/2016] [Indexed: 01/07/2023] Open
Abstract
In this report we show for the first time that neutron anomalous dispersion can be used in a practical manner to determine experimental phases of a protein crystal structure, providing a new tool for structural biologists. The approach is demonstrated through the use of a state-of-the-art monochromatic neutron diffractometer at the Institut Laue-Langevin (ILL) in combination with crystals of perdeuterated protein that minimise the level of hydrogen incoherent scattering and enhance the visibility of the anomalous signal. The protein used was rubredoxin in which cadmium replaced the iron at the iron-sulphur site. While this study was carried out using a steady-state neutron beam source, the results will be of major interest for capabilities at existing and emerging spallation neutron sources where time-of-flight instruments provide inherent energy discrimination. In particular this capability may be expected to offer unique opportunities to a rapidly developing structural biology community where there is increasing interest in the identification of protonation states, protein/water interactions and protein-ligand interactions - all of which are of central importance to a wide range of fundamental and applied areas in the biosciences.
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Affiliation(s)
- Maxime G. Cuypers
- Faculty of Natural Sciences, Keele University, Staffordshire, ST5 5BG, United Kingdom
- ILL, 71 avenue des Martyrs, 38000 Grenoble, France
| | - Sax A. Mason
- ILL, 71 avenue des Martyrs, 38000 Grenoble, France
| | - Estelle Mossou
- Faculty of Natural Sciences, Keele University, Staffordshire, ST5 5BG, United Kingdom
- ILL, 71 avenue des Martyrs, 38000 Grenoble, France
| | | | - V. Trevor Forsyth
- Faculty of Natural Sciences, Keele University, Staffordshire, ST5 5BG, United Kingdom
- ILL, 71 avenue des Martyrs, 38000 Grenoble, France
| | - Edward P. Mitchell
- Faculty of Natural Sciences, Keele University, Staffordshire, ST5 5BG, United Kingdom
- ESRF, 71 avenue des Martyrs, 38000 Grenoble, France
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86
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The use of neutron scattering to determine the functional structure of glycoside hydrolase. Curr Opin Struct Biol 2016; 40:54-61. [PMID: 27494120 DOI: 10.1016/j.sbi.2016.07.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 07/19/2016] [Accepted: 07/21/2016] [Indexed: 11/21/2022]
Abstract
Neutron diffraction provides different information from X-ray diffraction, because neutrons are scattered by atomic nuclei, whereas X-rays are scattered by electrons. One of the key advantages of neutron crystallography is the ability to visualize hydrogen and deuterium atoms, making it possible to observe the protonation state of amino acid residues, hydrogen bonds, networks of water molecules and proton relay pathways in enzymes. But, because of technical difficulties, less than 100 enzyme structures have been evaluated by neutron crystallography to date. In this review, we discuss the advantages and disadvantages of neutron crystallography as a tool to investigate the functional structure of glycoside hydrolases, with some examples.
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87
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O'Dell WB, Bodenheimer AM, Meilleur F. Neutron protein crystallography: A complementary tool for locating hydrogens in proteins. Arch Biochem Biophys 2016; 602:48-60. [DOI: 10.1016/j.abb.2015.11.033] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 11/12/2015] [Accepted: 11/16/2015] [Indexed: 10/22/2022]
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88
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Stranava M, Martínek V, Man P, Fojtikova V, Kavan D, Vaněk O, Shimizu T, Martinkova M. Structural characterization of the heme-based oxygen sensor, AfGcHK, its interactions with the cognate response regulator, and their combined mechanism of action in a bacterial two-component signaling system. Proteins 2016; 84:1375-89. [PMID: 27273553 DOI: 10.1002/prot.25083] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 05/19/2016] [Accepted: 05/30/2016] [Indexed: 01/11/2023]
Abstract
The oxygen sensor histidine kinase AfGcHK from the bacterium Anaeromyxobacter sp. Fw 109-5 forms a two-component signal transduction system together with its cognate response regulator (RR). The binding of oxygen to the heme iron of its N-terminal sensor domain causes the C-terminal kinase domain of AfGcHK to autophosphorylate at His183 and then transfer this phosphate to Asp52 or Asp169 of the RR protein. Analytical ultracentrifugation revealed that AfGcHK and the RR protein form a complex with 2:1 stoichiometry. Hydrogen-deuterium exchange coupled to mass spectrometry (HDX-MS) suggested that the most flexible part of the whole AfGcHK protein is a loop that connects the two domains and that the heme distal side of AfGcHK, which is responsible for oxygen binding, is the only flexible part of the sensor domain. HDX-MS studies on the AfGcHK:RR complex also showed that the N-side of the H9 helix in the dimerization domain of the AfGcHK kinase domain interacts with the helix H1 and the β-strand B2 area of the RR protein's Rec1 domain, and that the C-side of the H8 helix region in the dimerization domain of the AfGcHK protein interacts mostly with the helix H5 and β-strand B6 area of the Rec1 domain. The Rec1 domain containing the phosphorylable Asp52 of the RR protein probably has a significantly higher affinity for AfGcHK than the Rec2 domain. We speculate that phosphorylation at Asp52 changes the overall structure of RR such that the Rec2 area containing the second phosphorylation site (Asp169) can also interact with AfGcHK. Proteins 2016; 84:1375-1389. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Martin Stranava
- Department of Biochemistry, Charles University in Prague, Hlavova (Albertov) 2030-8, Prague 2, Czech Republic
| | - Václav Martínek
- Department of Biochemistry, Charles University in Prague, Hlavova (Albertov) 2030-8, Prague 2, Czech Republic.,Department of Chemical Education, Faculty of Science, Charles University in Prague, Hlavova (Albertov) 2030-8, Prague 2, Czech Republic
| | - Petr Man
- Department of Biochemistry, Charles University in Prague, Hlavova (Albertov) 2030-8, Prague 2, Czech Republic.,Laboratory of Structure Biology and Cell Signalling, BioCeV - Institute of Microbiology, Czech Academy of Sciences, V.V.I, Prumyslova 595, Vestec, Czech Republic
| | - Veronika Fojtikova
- Department of Biochemistry, Charles University in Prague, Hlavova (Albertov) 2030-8, Prague 2, Czech Republic
| | - Daniel Kavan
- Department of Biochemistry, Charles University in Prague, Hlavova (Albertov) 2030-8, Prague 2, Czech Republic.,Laboratory of Structure Biology and Cell Signalling, BioCeV - Institute of Microbiology, Czech Academy of Sciences, V.V.I, Prumyslova 595, Vestec, Czech Republic
| | - Ondřej Vaněk
- Department of Biochemistry, Charles University in Prague, Hlavova (Albertov) 2030-8, Prague 2, Czech Republic
| | - Toru Shimizu
- Department of Biochemistry, Charles University in Prague, Hlavova (Albertov) 2030-8, Prague 2, Czech Republic
| | - Marketa Martinkova
- Department of Biochemistry, Charles University in Prague, Hlavova (Albertov) 2030-8, Prague 2, Czech Republic.
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89
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Abstract
A detailed understanding of chemical and biological function and the mechanisms underlying the molecular activities ultimately requires atomic-resolution structural data. Diffraction-based techniques such as single-crystal X-ray crystallography, electron microscopy, and neutron diffraction are well established and they have paved the road to the stunning successes of modern-day structural biology. The major advances achieved in the last twenty years in all aspects of structural research, including sample preparation, crystallization, the construction of synchrotron and spallation sources, phasing approaches, and high-speed computing and visualization, now provide specialists and nonspecialists alike with a steady flow of molecular images of unprecedented detail. The present unit combines a general overview of diffraction methods with a detailed description of the process of a single-crystal X-ray structure determination experiment, from chemical synthesis or expression to phasing and refinement, analysis, and quality control. For novices it may serve as a stepping-stone to more in-depth treatises of the individual topics. Readers relying on structural information for interpreting functional data may find it a useful consumer guide. © 2016 by John Wiley & Sons, Inc.
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Affiliation(s)
- Martin Egli
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee
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90
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Gerlits O, Wymore T, Das A, Shen CH, Parks JM, Smith JC, Weiss KL, Keen DA, Blakeley MP, Louis JM, Langan P, Weber IT, Kovalevsky A. Long-Range Electrostatics-Induced Two-Proton Transfer Captured by Neutron Crystallography in an Enzyme Catalytic Site. Angew Chem Int Ed Engl 2016; 55:4924-7. [PMID: 26958828 DOI: 10.1002/anie.201509989] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 01/27/2016] [Indexed: 11/11/2022]
Abstract
Neutron crystallography was used to directly locate two protons before and after a pH-induced two-proton transfer between catalytic aspartic acid residues and the hydroxy group of the bound clinical drug darunavir, located in the catalytic site of enzyme HIV-1 protease. The two-proton transfer is triggered by electrostatic effects arising from protonation state changes of surface residues far from the active site. The mechanism and pH effect are supported by quantum mechanics/molecular mechanics (QM/MM) calculations. The low-pH proton configuration in the catalytic site is deemed critical for the catalytic action of this enzyme and may apply more generally to other aspartic proteases. Neutrons therefore represent a superb probe to obtain structural details for proton transfer reactions in biological systems at a truly atomic level.
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Affiliation(s)
- Oksana Gerlits
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Troy Wymore
- UT/ORNL Center for Molecular Biophysics, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Amit Das
- Solid State Physics Division, BARC, Trombay, Mumbai, 400085, India
| | - Chen-Hsiang Shen
- Departments of Chemistry and Biology, Georgia State University, Atlanta, GA, 30302, USA
| | - Jerry M Parks
- UT/ORNL Center for Molecular Biophysics, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Jeremy C Smith
- UT/ORNL Center for Molecular Biophysics, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Kevin L Weiss
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - David A Keen
- ISIS Facility, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, OX11 0QX, UK
| | - Matthew P Blakeley
- Large-Scale Structures Group, Institut Laue Langevin, 71 avenue des Martyrs - CS 20156, 38042, Grenoble Cedex 9, France
| | - John M Louis
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, DHHS, Bethesda, MD, 20892-0520, USA
| | - Paul Langan
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Irene T Weber
- Departments of Chemistry and Biology, Georgia State University, Atlanta, GA, 30302, USA
| | - Andrey Kovalevsky
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
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91
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Gerlits O, Wymore T, Das A, Shen CH, Parks JM, Smith JC, Weiss KL, Keen DA, Blakeley MP, Louis JM, Langan P, Weber IT, Kovalevsky A. Long-Range Electrostatics-Induced Two-Proton Transfer Captured by Neutron Crystallography in an Enzyme Catalytic Site. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201509989] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Oksana Gerlits
- Biology and Soft Matter Division; Oak Ridge National Laboratory; Oak Ridge TN 37831 USA
| | - Troy Wymore
- UT/ORNL Center for Molecular Biophysics; Biosciences Division; Oak Ridge National Laboratory; Oak Ridge TN 37831 USA
| | - Amit Das
- Solid State Physics Division; BARC; Trombay Mumbai 400085 India
| | - Chen-Hsiang Shen
- Departments of Chemistry and Biology; Georgia State University; Atlanta GA 30302 USA
| | - Jerry M. Parks
- UT/ORNL Center for Molecular Biophysics; Biosciences Division; Oak Ridge National Laboratory; Oak Ridge TN 37831 USA
| | - Jeremy C. Smith
- UT/ORNL Center for Molecular Biophysics; Biosciences Division; Oak Ridge National Laboratory; Oak Ridge TN 37831 USA
| | - Kevin L. Weiss
- Biology and Soft Matter Division; Oak Ridge National Laboratory; Oak Ridge TN 37831 USA
| | - David A. Keen
- ISIS Facility; Rutherford Appleton Laboratory; Harwell Oxford Didcot OX11 0QX UK
| | - Matthew P. Blakeley
- Large-Scale Structures Group; Institut Laue Langevin; 71 avenue des Martyrs - CS 20156 38042 Grenoble Cedex 9 France
| | - John M. Louis
- Laboratory of Chemical Physics; National Institute of Diabetes and Digestive and Kidney Diseases; National Institutes of Health, DHHS; Bethesda MD 20892-0520 USA
| | - Paul Langan
- Biology and Soft Matter Division; Oak Ridge National Laboratory; Oak Ridge TN 37831 USA
| | - Irene T. Weber
- Departments of Chemistry and Biology; Georgia State University; Atlanta GA 30302 USA
| | - Andrey Kovalevsky
- Biology and Soft Matter Division; Oak Ridge National Laboratory; Oak Ridge TN 37831 USA
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92
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Hosseinzadeh P, Mirts EN, Pfister TD, Gao YG, Mayne C, Robinson H, Tajkhorshid E, Lu Y. Enhancing Mn(II)-Binding and Manganese Peroxidase Activity in a Designed Cytochrome c Peroxidase through Fine-Tuning Secondary-Sphere Interactions. Biochemistry 2016; 55:1494-502. [PMID: 26885726 DOI: 10.1021/acs.biochem.5b01299] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Noncovalent second-shell interactions are important in controlling metal-binding affinity and activity in metalloenzymes, but fine-tuning these interactions in designed metalloenzymes has not been fully explored. As a result, most designed metalloenzymes have low metal-binding affinity and activity. Here we identified three mutations in the second coordination shell of an engineered Mn(II)-binding site in cytochrome c peroxidase (called MnCcP.1, containing Glu45, Glu37, and Glu181 ligands) that mimics the native manganese peroxidase (MnP), and explored their effects on both Mn(II)-binding affinity and MnP activity. First, removing a hydrogen bond to Glu45 through Tyr36Phe mutation enhanced Mn(II)-binding affinity, as evidenced by a 2.8-fold decrease in the KM of Mn(II) oxidation. Second, introducing a salt bridge through Lys179Arg mutation improved Glu35 and Glu181 coordination to Mn(II), decreasing KM 2.6-fold. Third, eliminating a steric clash that prevented Glu37 from orienting toward Mn(II) resulted in an 8.6-fold increase in kcat/KM, arising primarily from a 3.6-fold decrease in KM, with a KM value comparable to that of the native enzyme (0.28 mM vs 0.19 mM for Pleurotus eryngii MnP PS3). We further demonstrated that while the effects of Tyr36Phe and Lys179Arg mutations are additive, because involved in secondary-shell interactions to different ligands, other combinations of mutations were antagonistic because they act on different aspects of the Mn(II) coordination at the same residues. Finally, we showed that these MnCcP variants are functional models of MnP that mimic its activity in both Mn(II) oxidation and degradation of a phenolic lignin model compound and kraft lignin. In addition to achieving KM in a designed protein that is similar to the that of native enzyme, our results offer molecular insight into the role of noncovalent interactions around metal-binding sites for improving metal binding and overall activity; such insight can be applied to rationally enhance these properties in other metalloenzymes and their models.
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Affiliation(s)
| | | | | | | | | | - Howard Robinson
- Department of Biology, Brookhaven National Laboratory , Upton, New York 11973, United States
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93
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Crystal structure of the pristine peroxidase ferryl center and its relevance to proton-coupled electron transfer. Proc Natl Acad Sci U S A 2016; 113:1226-31. [PMID: 26787871 DOI: 10.1073/pnas.1521664113] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The reaction of peroxides with peroxidases oxidizes the heme iron from Fe(III) to Fe(IV)=O and a porphyrin or aromatic side chain to a cationic radical. X-ray-generated hydrated electrons rapidly reduce Fe(IV), thereby requiring very short exposures using many crystals, and, even then, some reduction cannot be avoided. The new generation of X-ray free electron lasers capable of generating intense X-rays on the tenths of femtosecond time scale enables structure determination with no reduction or X-ray damage. Here, we report the 1.5-Å crystal structure of cytochrome c peroxidase (CCP) compound I (CmpI) using data obtained with the Stanford Linear Coherent Light Source (LCLS). This structure is consistent with previous structures. Of particular importance is the active site water structure that can mediate the proton transfer reactions required for both CmpI formation and reduction of Fe(IV)=O to Fe(III)-OH. The structures indicate that a water molecule is ideally positioned to shuttle protons between an iron-linked oxygen and the active site catalytic His. We therefore have carried out both computational and kinetic studies to probe the reduction of Fe(IV)=O. Kinetic solvent isotope experiments show that the transfer of a single proton is critical in the peroxidase rate-limiting step, which is very likely the proton-coupled reduction of Fe(IV)=O to Fe(III)-OH. We also find that the pKa of the catalytic His substantially increases in CmpI, indicating that this active site His is the source of the proton required in the reduction of Fe(IV)=O to Fe(IV)-OH.
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94
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Haertlein M, Moulin M, Devos JM, Laux V, Dunne O, Trevor Forsyth V. Biomolecular Deuteration for Neutron Structural Biology and Dynamics. Methods Enzymol 2016; 566:113-57. [DOI: 10.1016/bs.mie.2015.11.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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95
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Abstract
A common structural motif in heme proteins is a five-coordinate species in which the iron is coordinated by a histidyl residue. The widely distributed heme proteins with this motif are essential for the well being of humans and other organisms. We detail the differences in molecular structures and physical properties of high-spin iron(ii) porphyrin derivatives ligated by neutral imidazole, hydrogen bonded imidazole, and imidazolate or other anions. Two distinct (high spin) electronic states are observed that have differing d-orbital occupancies and discernibly different five-coordinate square-pyramidal coordination groups. The doubly occupied orbital in the imidazole species is a low symmetry orbital oblique to the heme plane whereas in the imidazolate species the doubly occupied orbital is a high symmetry orbital in the heme plane, i.e., the primary doubly-occupied d-orbital is different. Methods that can be used to classify a particular complex into one or the other state include X-ray structure determinations, high-field Mössbauer spectroscopy, vibrational spectroscopy, magnetic circular dichroism, and even-spin EPR spectroscopy. The possible functional significance of the ground state differences has not been established for heme proteins, but is likely found in the pathways for oxygen transport vs. oxygen utilization.
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96
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Smith DA, Beweries T, Blasius C, Jasim N, Nazir R, Nazir S, Robertson CC, Whitwood AC, Hunter CA, Brammer L, Perutz RN. The Contrasting Character of Early and Late Transition Metal Fluorides as Hydrogen Bond Acceptors. J Am Chem Soc 2015; 137:11820-31. [DOI: 10.1021/jacs.5b07509] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dan A. Smith
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
| | - Torsten Beweries
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
| | - Clemens Blasius
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
| | - Naseralla Jasim
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
| | - Ruqia Nazir
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
| | - Sadia Nazir
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
| | - Craig C. Robertson
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, U.K
| | - Adrian C. Whitwood
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
| | | | - Lee Brammer
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, U.K
| | - Robin N. Perutz
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, U.K
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97
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Campomanes P, Rothlisberger U, Alfonso-Prieto M, Rovira C. The Molecular Mechanism of the Catalase-like Activity in Horseradish Peroxidase. J Am Chem Soc 2015; 137:11170-8. [DOI: 10.1021/jacs.5b06796] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Pablo Campomanes
- Laboratory
of Computational Chemistry and Biochemistry, Institute of Chemical
Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Ursula Rothlisberger
- Laboratory
of Computational Chemistry and Biochemistry, Institute of Chemical
Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Mercedes Alfonso-Prieto
- Departament de Química Orgànica & Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Martí i Franquès 1, 08208 Barcelona, Spain
| | - Carme Rovira
- Departament de Química Orgànica & Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Martí i Franquès 1, 08208 Barcelona, Spain
- Institució
Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys, 23, 08018 Barcelona, Spain
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98
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Coates L, Cuneo MJ, Frost MJ, He J, Weiss KL, Tomanicek SJ, McFeeters H, Vandavasi VG, Langan P, Iverson EB. The Macromolecular Neutron Diffractometer MaNDi at the Spallation Neutron Source. J Appl Crystallogr 2015. [DOI: 10.1107/s1600576715011243] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The Macromolecular Neutron Diffractometer (MaNDi) is located on beamline 11B of the Spallation Neutron Source at Oak Ridge National Laboratory. The instrument is a neutron time-of-flight wavelength-resolved Laue diffractometer optimized to collect diffraction data from single crystals. The instrument has been designed to provide flexibility in several instrumental parameters, such as beam divergence and wavelength bandwidth, to allow data collection from a range of macromolecular systems.
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99
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Blakeley MP, Hasnain SS, Antonyuk SV. Sub-atomic resolution X-ray crystallography and neutron crystallography: promise, challenges and potential. IUCRJ 2015; 2:464-74. [PMID: 26175905 PMCID: PMC4491318 DOI: 10.1107/s2052252515011239] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 06/09/2015] [Indexed: 05/20/2023]
Abstract
The International Year of Crystallography saw the number of macromolecular structures deposited in the Protein Data Bank cross the 100000 mark, with more than 90000 of these provided by X-ray crystallography. The number of X-ray structures determined to sub-atomic resolution (i.e. ≤1 Å) has passed 600 and this is likely to continue to grow rapidly with diffraction-limited synchrotron radiation sources such as MAX-IV (Sweden) and Sirius (Brazil) under construction. A dozen X-ray structures have been deposited to ultra-high resolution (i.e. ≤0.7 Å), for which precise electron density can be exploited to obtain charge density and provide information on the bonding character of catalytic or electron transfer sites. Although the development of neutron macromolecular crystallography over the years has been far less pronounced, and its application much less widespread, the availability of new and improved instrumentation, combined with dedicated deuteration facilities, are beginning to transform the field. Of the 83 macromolecular structures deposited with neutron diffraction data, more than half (49/83, 59%) were released since 2010. Sub-mm(3) crystals are now regularly being used for data collection, structures have been determined to atomic resolution for a few small proteins, and much larger unit-cell systems (cell edges >100 Å) are being successfully studied. While some details relating to H-atom positions are tractable with X-ray crystallography at sub-atomic resolution, the mobility of certain H atoms precludes them from being located. In addition, highly polarized H atoms and protons (H(+)) remain invisible with X-rays. Moreover, the majority of X-ray structures are determined from cryo-cooled crystals at 100 K, and, although radiation damage can be strongly controlled, especially since the advent of shutterless fast detectors, and by using limited doses and crystal translation at micro-focus beams, radiation damage can still take place. Neutron crystallography therefore remains the only approach where diffraction data can be collected at room temperature without radiation damage issues and the only approach to locate mobile or highly polarized H atoms and protons. Here a review of the current status of sub-atomic X-ray and neutron macromolecular crystallography is given and future prospects for combined approaches are outlined. New results from two metalloproteins, copper nitrite reductase and cytochrome c', are also included, which illustrate the type of information that can be obtained from sub-atomic-resolution (∼0.8 Å) X-ray structures, while also highlighting the need for complementary neutron studies that can provide details of H atoms not provided by X-ray crystallography.
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Affiliation(s)
- Matthew P. Blakeley
- Large-Scale Structures Group, Institut Laue-Langevin, 71 Avenue des Martyrs, Grenoble 38000, France
| | - Samar S. Hasnain
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZX, UK
| | - Svetlana V. Antonyuk
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZX, UK
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100
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Chreifi G, Hollingsworth SA, Li H, Tripathi S, Arce AP, Magaña-Garcia HI, Poulos TL. Enzymatic Mechanism of Leishmania major Peroxidase and the Critical Role of Specific Ionic Interactions. Biochemistry 2015; 54:3328-36. [PMID: 25941976 DOI: 10.1021/acs.biochem.5b00338] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Leishmania major peroxidase (LmP) is very similar to the well-known yeast cytochrome c peroxidase (CcP). Both enzymes catalyze the peroxidation of cytochrome c. Like CcP, LmP reacts with H2O2 to form Compound I, which consists of a ferryl heme and a Trp radical, Fe(IV)═O;Trp(•+). Cytochrome c (Cytc) reduces the Trp radical to give Compound II, Fe(IV)═O;Trp, which is followed by an intramolecular electron transfer to give Fe(III)-OH;Trp(•+), and in the last step, Cytc reduces the Trp radical. In this study, we have used steady-state and single-turnover kinetics to improve our understanding of the overall mechanism of LmP catalysis. While the activity of CcP greatly increases with ionic strength, the kcat for LmP remains relatively constant at all ionic strengths tested. Therefore, unlike CcP, where dissociation of oxidized Cytc is limiting at low ionic strengths, association/dissociation reactions are not limiting at any ionic strength in LmP. We conclude that in LmP, the intramolecular electron transfer reaction, Fe(IV)═O;Trp to Fe(III)-OH;Trp(•+), is limiting at all ionic strengths. Unlike CcP, LmP depends on key intermolecular ion pairs to form the electron transfer competent complex. Mutating these sites causes the initial rate of association to decrease by 2 orders of magnitude and a substantial decrease in kcat. The drop in kcat is due to a switch in the rate-limiting step of the mutants from intramolecular electron transfer to the rate of association in forming the LmP-LmCytc complex. These studies show that while LmP and CcP form very similar complexes and exhibit similar activities, they substantially differ in how their activity changes as a function of ionic strength. This difference is primarily due to the heavy reliance of LmP on highly specific intermolecular ion pairs, while CcP relies mainly on nonpolar interactions.
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Affiliation(s)
- Georges Chreifi
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Scott A Hollingsworth
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Huiying Li
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Sarvind Tripathi
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Anton P Arce
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Hugo I Magaña-Garcia
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
| | - Thomas L Poulos
- †Department of Molecular Biology and Biochemistry, ‡Department of Chemistry, and §Department of Pharmaceutical Sciences, University of California, Irvine, California 92697-3900, United States
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