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Transcriptome Analysis of the Acid Stress Response of Desulfovibrio vulgaris ATCC 7757. Curr Microbiol 2020; 77:2702-2712. [DOI: 10.1007/s00284-020-02051-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 05/23/2020] [Indexed: 01/23/2023]
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Pelmenschikov V, Birrell JA, Pham CC, Mishra N, Wang H, Sommer C, Reijerse E, Richers CP, Tamasaku K, Yoda Y, Rauchfuss TB, Lubitz W, Cramer SP. Reaction Coordinate Leading to H 2 Production in [FeFe]-Hydrogenase Identified by Nuclear Resonance Vibrational Spectroscopy and Density Functional Theory. J Am Chem Soc 2017; 139:16894-16902. [PMID: 29054130 PMCID: PMC5699932 DOI: 10.1021/jacs.7b09751] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
[FeFe]-hydrogenases are metalloenzymes that reversibly reduce protons to molecular hydrogen at exceptionally high rates. We have characterized the catalytically competent hydride state (Hhyd) in the [FeFe]-hydrogenases from both Chlamydomonas reinhardtii and Desulfovibrio desulfuricans using 57Fe nuclear resonance vibrational spectroscopy (NRVS) and density functional theory (DFT). H/D exchange identified two Fe-H bending modes originating from the binuclear iron cofactor. DFT calculations show that these spectral features result from an iron-bound terminal hydride, and the Fe-H vibrational frequencies being highly dependent on interactions between the amine base of the catalytic cofactor with both hydride and the conserved cysteine terminating the proton transfer chain to the active site. The results indicate that Hhyd is the catalytic state one step prior to H2 formation. The observed vibrational spectrum, therefore, provides mechanistic insight into the reaction coordinate for H2 bond formation by [FeFe]-hydrogenases.
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Affiliation(s)
- Vladimir Pelmenschikov
- Institut für Chemie, Technische Universität Berlin , Strasse des 17 Juni 135, 10623 Berlin, Germany
| | - James A Birrell
- Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Cindy C Pham
- Department of Chemistry, University of California, Davis , One Shields Avenue, Davis, California 95616, United States
| | - Nakul Mishra
- Department of Chemistry, University of California, Davis , One Shields Avenue, Davis, California 95616, United States
| | - Hongxin Wang
- Department of Chemistry, University of California, Davis , One Shields Avenue, Davis, California 95616, United States
| | - Constanze Sommer
- Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Edward Reijerse
- Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Casseday P Richers
- School of Chemical Sciences, University of Illinois , 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Kenji Tamasaku
- JASRI , Spring-8, 1-1-1 Kouto, Mikazuki-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - Yoshitaka Yoda
- JASRI , Spring-8, 1-1-1 Kouto, Mikazuki-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - Thomas B Rauchfuss
- School of Chemical Sciences, University of Illinois , 600 S. Mathews Avenue, Urbana, Illinois 61801, United States
| | - Wolfgang Lubitz
- Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Stephen P Cramer
- Department of Chemistry, University of California, Davis , One Shields Avenue, Davis, California 95616, United States
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Sommer C, Adamska-Venkatesh A, Pawlak K, Birrell JA, Rüdiger O, Reijerse EJ, Lubitz W. Proton Coupled Electronic Rearrangement within the H-Cluster as an Essential Step in the Catalytic Cycle of [FeFe] Hydrogenases. J Am Chem Soc 2017; 139:1440-1443. [PMID: 28075576 DOI: 10.1021/jacs.6b12636] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The active site of [FeFe] hydrogenases, the H-cluster, consists of a [4Fe-4S] cluster connected via a bridging cysteine to a [2Fe] complex carrying CO and CN- ligands as well as a bridging aza-dithiolate ligand (ADT) of which the amine moiety serves as a proton shuttle between the protein and the H-cluster. During the catalytic cycle, the two subclusters change oxidation states: [4Fe-4S]H2+ ⇔ [4Fe-4S]H+ and [Fe(I)Fe(II)]H ⇔ [Fe(I)Fe(I)]H thereby enabling the storage of the two electrons needed for the catalyzed reaction 2H+ + 2e- ⇄ H2. Using FTIR spectro-electrochemistry on the [FeFe] hydrogenase from Chlamydomonas reinhardtii (CrHydA1) at different pH values, we resolve the redox and protonation events in the catalytic cycle and determine their intrinsic thermodynamic parameters. We show that the singly reduced state Hred of the H-cluster actually consists of two species: Hred = [4Fe-4S]H+ - [Fe(I)Fe(II)]H and HredH+ = [4Fe-4S]H2+ - [Fe(I)Fe(I)]H (H+) related by proton coupled electronic rearrangement. The two redox events in the catalytic cycle occur on the [4Fe-4S]H subcluster at similar midpoint-potentials (-375 vs -418 mV); the protonation event (Hred/HredH+) has a pKa ≈ 7.2.
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Affiliation(s)
- Constanze Sommer
- Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany
| | | | - Krzysztof Pawlak
- Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany
| | - James A Birrell
- Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany
| | - Olaf Rüdiger
- Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany
| | - Edward J Reijerse
- Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany
| | - Wolfgang Lubitz
- Max-Planck-Institut für Chemische Energiekonversion , Stiftstrasse 34-36, 45470 Mülheim/Ruhr, Germany
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Birrell JA, Wrede K, Pawlak K, Rodriguez-Maciá P, Rüdiger O, Reijerse EJ, Lubitz W. Artificial Maturation of the Highly Active Heterodimeric [FeFe] Hydrogenase from Desulfovibrio desulfuricans
ATCC 7757. Isr J Chem 2016. [DOI: 10.1002/ijch.201600035] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- James A. Birrell
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Kathrin Wrede
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Krzysztof Pawlak
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Patricia Rodriguez-Maciá
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Olaf Rüdiger
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Edward J. Reijerse
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
| | - Wolfgang Lubitz
- Max Planck Institute for Chemical Energy Conversion; Stiftstraße 34-36 D-45470 Mülheim an der Ruhr Germany
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Reardon CL, Magnuson TS, Boyd ES, Leavitt WD, Reed DW, Geesey GG. Hydrogenase activity of mineral-associated and suspended populations of Desulfovibrio desulfuricans Essex 6. MICROBIAL ECOLOGY 2014; 67:318-326. [PMID: 24194097 DOI: 10.1007/s00248-013-0308-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 10/02/2013] [Indexed: 06/02/2023]
Abstract
The interactions between sulfate-reducing microorganisms and iron oxides influence a number of important redox-sensitive biogeochemical processes including the formation of iron sulfides. Enzymes, such as hydrogenase which catalyze the reversible oxidation of molecular hydrogen, are known to mediate electron transfer to metals and may contribute to the formation and speciation of ferrous sulfides formed at the cell-mineral interface. In the present study, we compared the whole cell hydrogenase activity of Desulfovibrio desulfuricans strain Essex 6 growing as biofilms on hematite (hematite-associated) or as suspended populations using different metabolic pathways. Hematite-associated cells exhibited significantly greater hydrogenase activity than suspended populations during sulfate respiration but not during pyruvate fermentation. The enhanced activity of the hematite-associated, sulfate-grown cells appears to be dependent on iron availability rather than a general response to surface attachment since the activity of glass-associated cells did not differ from that of suspended populations. Hydrogenase activity of pyruvate-fermenting cells was stimulated by addition of iron as soluble Fe(II)Cl2 and, in the absence of added iron, both sulfate-reducing and pyruvate-fermenting cells displayed similar rates of hydrogenase activity. These data suggest that iron exerts a stronger influence on whole cell hydrogenase activity than either metabolic pathway or mode of growth. The location of hydrogenase to the cell envelope and the enhanced activity at the hematite surface in sulfate-reducing cells may influence the redox conditions that control the species of iron sulfides on the mineral surface.
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Affiliation(s)
- C L Reardon
- Columbia Plateau Conservation Research Center, USDA Agricultural Research Service, Adams, OR, 97810, USA,
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Greco C, Bruschi M, Fantucci P, Ryde U, De Gioia L. Probing the Effects of One-Electron Reduction and Protonation on the Electronic Properties of the Fe-S Clusters in the Active-Ready Form of [FeFe]-Hydrogenases. A QM/MM Investigation. Chemphyschem 2011; 12:3376-82. [DOI: 10.1002/cphc.201100498] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 10/13/2011] [Indexed: 11/08/2022]
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Greco C, Bruschi M, Fantucci P, Ryde U, De Gioia L. Mechanistic and Physiological Implications of the Interplay among Iron–Sulfur Clusters in [FeFe]-Hydrogenases. A QM/MM Perspective. J Am Chem Soc 2011; 133:18742-9. [DOI: 10.1021/ja205542k] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- Claudio Greco
- Department of Biotechnology and Bioscience, University of Milan-Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
- Department of Chemistry, Humboldt-Universitaet zu Berlin, Brook-Taylor-Strasse 2, 12489, Berlin, Germany
| | - Maurizio Bruschi
- Department of Environmental Sciences, University of Milan-Bicocca, Piazza della Scienza 1, 20126, Milan, Italy
| | - Piercarlo Fantucci
- Department of Biotechnology and Bioscience, University of Milan-Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
| | - Ulf Ryde
- Department of Theoretical Chemistry, Lund University, P.O. Box 124, 22100 Lund, Sweden
| | - Luca De Gioia
- Department of Biotechnology and Bioscience, University of Milan-Bicocca, Piazza della Scienza 2, 20126, Milan, Italy
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Hoge R, Laschinski M, Jaeger KE, Wilhelm S, Rosenau F. The subcellular localization of a C-terminal processing protease in Pseudomonas aeruginosa. FEMS Microbiol Lett 2011; 316:23-30. [PMID: 21204920 DOI: 10.1111/j.1574-6968.2010.02181.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Carboxy (C)-terminal processing proteases (CTP) are a relatively new group of serine proteases. Found in a broad range of organisms - bacteria, archaea, algae, plants and animals - these proteases are involved in the C-terminal processing of proteins. In comparison with amino-terminal processing of bacterial proteins, less is known about C-terminal processing and its physiological function. Bacterial CTPs appear to influence different basal cellular processes. Although CTPs of Gram-negative bacteria are generally referred to as being localized in the periplasm, there is little experimental evidence for this. We show for the first time the subcellular localization of a CTP-3 family protein from Pseudomonas aeruginosa, named CtpA, in the periplasm by a carefully designed fractionation study. Our results provide experimental evidence for the generally accepted hypothesis that CTPs are located in the periplasmic space of Gram-negative bacteria.
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Affiliation(s)
- Rien Hoge
- Research Centre Juelich, Institute for Molecular Enzyme Technology, Heinrich-Heine-University Duesseldorf, Juelich, Germany.
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9
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Peters JW. Carbon Monoxide and Cyanide Ligands in the Active Site of [FeFe]-Hydrogenases. METAL-CARBON BONDS IN ENZYMES AND COFACTORS 2009. [DOI: 10.1039/9781847559333-00179] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The [FeFe]-hydrogenases, although share common features when compared to other metal containing hydrogenases, clearly have independent evolutionary origins. Examples of [FeFe]-hydrogenases have been characterized in detail by biochemical and spectroscopic approaches and the high resolution structures of two examples have been determined. The active site H-cluster is a complex bridged metal assembly in which a [4Fe-4S] cubane is bridged to a 2Fe subcluster with unique non-protein ligands including carbon monoxide, cyanide, and a five carbon dithiolate. Carbon monoxide and cyanide ligands as a component of a native active metal center is a property unique to the metal containing hydrogenases and there has been considerable attention to the characterization of the H-cluster at the level of electronic structure and mechanism as well as to defining the biological means to synthesize such a unique metal cluster. The chapter describes the structural architecture of [FeFe]-hydrogenases and key spectroscopic observations that have afforded the field with a fundamental basis for understanding the relationship between structure and reactivity of the H-cluster. In addition, the results and ideas concerning the topic of H-cluster biosynthesis as an emerging and fascinating area of research, effectively reinforcing the potential linkage between iron-sulfur biochemistry to the role of iron-sulfur minerals in prebiotic chemistry and the origin of life.
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Affiliation(s)
- John W. Peters
- Montana State University, Department of Chemistry and Biochemistry and the Astrobiology Biogeocatalysis Research Center Bozeman, MT 59717 USA
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10
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Silakov A, Wenk B, Reijerse E, Albracht SPJ, Lubitz W. Spin distribution of the H-cluster in the Hox–CO state of the [FeFe] hydrogenase from Desulfovibrio desulfuricans: HYSCORE and ENDOR study of 14N and 13C nuclear interactions. J Biol Inorg Chem 2008; 14:301-13. [DOI: 10.1007/s00775-008-0449-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2008] [Accepted: 11/02/2008] [Indexed: 10/21/2022]
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Vignais PM, Billoud B. Occurrence, Classification, and Biological Function of Hydrogenases: An Overview. Chem Rev 2007; 107:4206-72. [PMID: 17927159 DOI: 10.1021/cr050196r] [Citation(s) in RCA: 1039] [Impact Index Per Article: 61.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Paulette M. Vignais
- CEA Grenoble, Laboratoire de Biochimie et Biophysique des Systèmes Intégrés, UMR CEA/CNRS/UJF 5092, Institut de Recherches en Technologies et Sciences pour le Vivant (iRTSV), 17 rue des Martyrs, 38054 Grenoble cedex 9, France, and Atelier de BioInformatique Université Pierre et Marie Curie (Paris 6), 12 rue Cuvier, 75005 Paris, France
| | - Bernard Billoud
- CEA Grenoble, Laboratoire de Biochimie et Biophysique des Systèmes Intégrés, UMR CEA/CNRS/UJF 5092, Institut de Recherches en Technologies et Sciences pour le Vivant (iRTSV), 17 rue des Martyrs, 38054 Grenoble cedex 9, France, and Atelier de BioInformatique Université Pierre et Marie Curie (Paris 6), 12 rue Cuvier, 75005 Paris, France
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12
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Fontecilla-Camps JC, Volbeda A, Cavazza C, Nicolet Y. Structure/function relationships of [NiFe]- and [FeFe]-hydrogenases. Chem Rev 2007; 107:4273-303. [PMID: 17850165 DOI: 10.1021/cr050195z] [Citation(s) in RCA: 1004] [Impact Index Per Article: 59.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Juan C Fontecilla-Camps
- Laboratoire de Cristallographie et Cristallogenèse des Proteines, Institut de Biologie Structurale J. P. Ebel, CEA, CNRS, Universitè Joseph Fourier, 41 rue J. Horowitz, 38027 Grenoble Cedex 1, France.
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13
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Lubitz W, Reijerse E, van Gastel M. [NiFe] and [FeFe] Hydrogenases Studied by Advanced Magnetic Resonance Techniques. Chem Rev 2007; 107:4331-65. [PMID: 17845059 DOI: 10.1021/cr050186q] [Citation(s) in RCA: 376] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Wolfgang Lubitz
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, D-45470 Mülheim an der Ruhr, Germany
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Silakov A, Reijerse EJ, Albracht SPJ, Hatchikian EC, Lubitz W. The Electronic Structure of the H-Cluster in the [FeFe]-Hydrogenase from Desulfovibrio desulfuricans: A Q-band 57Fe-ENDOR and HYSCORE Study. J Am Chem Soc 2007; 129:11447-58. [PMID: 17722921 DOI: 10.1021/ja072592s] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The active site of the (57)Fe-enriched [FeFe]-hydrogenase (i.e., the "H-cluster") from Desulfovibrio desulfuricans has been examined using advanced pulse EPR methods at X- and Q-band frequencies. For both the active oxidized state (H(ox)) and the CO inhibited form (H(ox)-CO) all six (57)Fe hyperfine couplings were detected. The analysis shows that the apparent spin density extends over the whole H-cluster. The investigations revealed different hyperfine couplings of all six (57)Fe nuclei in the H-cluster of the H(ox)-CO state. Four large 57Fe hyperfine couplings in the range 20-40 MHz were found (using pulse ENDOR and TRIPLE methods) and were assigned to the [4Fe-4S](H) (cubane) subcluster. Two weak (57)Fe hyperfine couplings below 5 MHz were identified using Q-band HYSCORE spectroscopy and were assigned to the [2Fe](H) subcluster. For the H(ox) state only two different 57Fe hyperfine couplings in the range 10-13 MHz were detected using pulse ENDOR. An (57)Fe line broadening analysis of the X-band CW EPR spectrum indicated, however, that all six (57)Fe nuclei in the H-cluster are contributing to the hyperfine pattern. It is concluded that in both states the binuclear subcluster [2Fe](H) assumes a [Fe(I)Fe(II)] redox configuration where the paramagnetic Fe(I) atom is attached to the [4Fe-4S](H) subcluster. The (57)Fe hyperfine interactions of the formally diamagnetic [4Fe-4S](H) are due to an exchange interaction between the two subclusters as has been discussed earlier by Popescu and Münck [Popescu, C.V.; Münck, E., J. Am. Chem. Soc. 1999, 121, 7877-7884]. This exchange coupling is strongly enhanced by binding of the extrinsic CO ligand. Binding of the dihydrogen substrate may induce a similar effect, and it is therefore proposed that the observed modulation of the electronic structure by the changing ligand surrounding plays an important role in the catalytic mechanism of [FeFe]-hydrogenase.
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Affiliation(s)
- Alexey Silakov
- Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, Mülheim a. d. Ruhr, 45470, Germany
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Parkin A, Cavazza C, Fontecilla-Camps JC, Armstrong FA. Electrochemical Investigations of the Interconversions between Catalytic and Inhibited States of the [FeFe]-Hydrogenase from Desulfovibrio desulfuricans. J Am Chem Soc 2006; 128:16808-15. [PMID: 17177431 DOI: 10.1021/ja064425i] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Studies of the catalytic properties of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans by protein film voltammetry, under a H2 atmosphere, reveal and establish a variety of interesting properties not observed or measured quantitatively with other techniques. The catalytic bias (inherent ability to oxidize hydrogen vs reduce protons) is quantified over a wide pH range: the enzyme is proficient at both H2 oxidation (from pH > 6) and H2 production (pH < 6). Hydrogen production is inhibited by H2, but the effect is much smaller than observed for [NiFe]-hydrogenases from Allochromatium vinosum or Desulfovibrio fructosovorans. Under anaerobic conditions and positive potentials, the [FeFe]-hydrogenase is oxidized to an inactive form, inert toward reaction with CO and O2, that rapidly reactivates upon one-electron reduction under 1 bar of H2. The potential dependence of this interconversion shows that the oxidized inactive form exists in two pH-interconvertible states with pK(ox) = 5.9. Studies of the CO-inhibited enzyme under H2 reveals a strong enhancement of the rate of activation by white light at -109 mV (monitoring H2 oxidation) that is absent at low potential (-540 mV, monitoring H+ reduction), thus demonstrating photolability that is dependent upon the oxidation state.
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Affiliation(s)
- Alison Parkin
- Inorganic Chemistry Laboratory, Department of Chemistry, Oxford University, South Parks Road, Oxford OX1 3QR, England
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Vincent KA, Parkin A, Lenz O, Albracht SPJ, Fontecilla-Camps JC, Cammack R, Friedrich B, Armstrong FA. Electrochemical definitions of O2 sensitivity and oxidative inactivation in hydrogenases. J Am Chem Soc 2006; 127:18179-89. [PMID: 16366571 DOI: 10.1021/ja055160v] [Citation(s) in RCA: 156] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new strategy is described for comparing, quantitatively, the ability of hydrogenases to tolerate exposure to O2 and anoxic oxidizing conditions. Using protein film voltammetry, the inherent sensitivities to these challenges (thermodynamic potentials and rates of reactions) have been measured for enzymes from a range of mesophilic microorganisms. In the absence of O2, all the hydrogenases undergo reversible inactivation at various potentials above that of the H+/H2 redox couple, and H2 oxidation activities are thus limited to characteristic "potential windows". Reactions with O2 vary greatly; the [FeFe]-hydrogenase from Desulfovibrio desulfuricans ATCC 7757, an anaerobe, is irreversibly damaged by O2, surviving only if exposed to O2 in the anaerobically oxidized state (which therefore affords protection). In contrast, the membrane-bound [NiFe]-hydrogenase from the aerobe, Ralstonia eutropha, reacts reversibly with O2 even during turnover and continues to catalyze H2 oxidation in the presence of O2.
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Affiliation(s)
- Kylie A Vincent
- Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, UK
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17
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Roseboom W, De Lacey AL, Fernandez VM, Hatchikian EC, Albracht SPJ. The active site of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans. II. Redox properties, light sensitivity and CO-ligand exchange as observed by infrared spectroscopy. J Biol Inorg Chem 2005; 11:102-18. [PMID: 16323019 DOI: 10.1007/s00775-005-0040-2] [Citation(s) in RCA: 180] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Accepted: 09/26/2005] [Indexed: 10/25/2022]
Abstract
In [FeFe]-hydrogenases, the H cluster (hydrogen-activating cluster) contains a di-iron centre ([2Fe]H subcluster, a (L)(CO)(CN)Fe(mu-RS2)(mu-CO)Fe(CysS)(CO)(CN) group) covalently attached to a cubane iron-sulphur cluster ([4Fe-4S]H subcluster). The Cys-thiol functions as the link between one iron (called Fe1) of the [2Fe]H subcluster and one iron of the cubane subcluster. The other iron in the [2Fe]H subcluster is called Fe2. The light sensitivity of the Desulfovibrio desulfuricans enzyme in a variety of states has been studied with infrared (IR) spectroscopy. The aerobic inactive enzyme (H(inact) state) and the CO-inhibited active form (H(ox)-CO state) were stable in light. Illumination of the H(ox) state led to a kind of cannibalization; in some enzyme molecules the H cluster was destroyed and the released CO was captured by the H clusters in other molecules to form the light-stable H(ox)-CO state. Illumination of active enzyme under 13CO resulted in the complete exchange of the two intrinsic COs bound to Fe2. At cryogenic temperatures, light induced the photodissociation of the extrinsic CO and the bridging CO of the enzyme in the H(ox)-CO state. Electrochemical redox titrations showed that the enzyme in the H(inact) state converts to the transition state (H(trans)) in a reversible one-electron redox step (E (m, pH 7) = -75 mV). IR spectra demonstrate that the added redox equivalent not only affects the [4Fe-4S]H subcluster, but also the di-iron centre. Enzyme in the H(trans) state reacts with extrinsic CO, which binds to Fe2. The H(trans) state converts irreversibly into the H(ox) state in a redox-dependent reaction most likely involving two electrons (E (m, pH 7) = -261 mV). These electrons do not end up on any of the six Fe atoms of the H cluster; the possible destiny of the two redox equivalents is discussed. An additional reversible one-electron redox reaction leads to the H(red) state (E (m, pH 7) = -354 mV), where both Fe atoms of the [2Fe]H subcluster have the same formal oxidation state. The possible oxidation states of Fe1 and Fe2 in the various enzyme states are discussed. Low redox potentials (below -500 mV) lead to destruction of the [2Fe]H subcluster.
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Affiliation(s)
- Winfried Roseboom
- Swammerdam Institute for Life Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands
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Albracht SPJ, Roseboom W, Hatchikian EC. The active site of the [FeFe]-hydrogenase from Desulfovibrio desulfuricans. I. Light sensitivity and magnetic hyperfine interactions as observed by electron paramagnetic resonance. J Biol Inorg Chem 2005; 11:88-101. [PMID: 16323020 DOI: 10.1007/s00775-005-0039-8] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Accepted: 09/26/2005] [Indexed: 10/25/2022]
Abstract
The hydrogen-activating cluster (H cluster) in [FeFe]-hydrogenases consists of two moieties. The [2Fe]H subcluster is a (L)(CO)(CN)Fe(mu-RS2)(mu-CO)Fe(CysS)(CO)(CN) centre. The Cys-bound Fe is called Fe1, the other iron Fe2. The Cys-thiol forms a bridge to a [4Fe-4S] cluster, the [4Fe-4S]H subcluster. We report that electron paramagnetic resonance (EPR) spectra of the 57Fe-enriched enzyme from Desulfovibrio desulfuricans in the H(ox)-CO state are consistent with a magnetic hyperfine interaction of the unpaired spin with all six Fe atoms of the H cluster. In contrast to the inactive aerobic enzyme, the active enzyme is easily destroyed by light. The [2Fe]H subcluster in some enzyme molecules loses CO by photolysis, whereupon other molecules firmly bind the released CO to form the H(ox)-CO state giving rise to the so-called axial 2.06 EPR signal. Though not destroyed by light, the H(ox)-CO state is affected by it. As demonstrated in the accompanying paper [49] two of the intrinsic COs, both bound to Fe2, can be exchanged by extrinsic 13CO during illumination at 2 degrees C. We found that only one of the three 13COs, the one at the extrinsic position, gives an EPR-detectable isotropic superhyperfine interaction of 0.6 mT. At 30 K both the inhibiting extrinsic CO bound to Fe2 and one more CO can be photolysed. EPR spectra of the photolysed products are consistent with a 3d7 system of Fe with the formal oxidation state +1. The damaged enzyme shows a light-sensitive g = 5 signal which is ascribed to an S = 3/2 form of the [2Fe](H) subcluster. The light sensitivity of the enzyme explains the occurrence of the g = 5 signal and the axial 2.06 signal in published EPR spectra of nearly all preparations studied thus far.
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Affiliation(s)
- Simon P J Albracht
- Swammerdam Institute for Life Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV, Amsterdam, The Netherlands,
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Ostberg Y, Carroll JA, Pinne M, Krum JG, Rosa P, Bergström S. Pleiotropic effects of inactivating a carboxyl-terminal protease, CtpA, in Borrelia burgdorferi. J Bacteriol 2004; 186:2074-84. [PMID: 15028692 PMCID: PMC374408 DOI: 10.1128/jb.186.7.2074-2084.2004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2003] [Accepted: 12/01/2003] [Indexed: 11/20/2022] Open
Abstract
A gene encoding a putative carboxyl-terminal protease (CtpA), an unusual type of protease, is present in the Borrelia burgdorferi B31 genome. The B. burgdorferi CtpA amino acid sequence exhibits similarities to the sequences of the CtpA enzymes of the cyanobacterium Synechocystis sp. strain PCC 6803 and higher plants and also exhibits similarities to the sequences of putative CtpA proteins in other bacterial species. Here, we studied the effect of ctpA gene inactivation on the B. burgdorferi protein expression profile. Total B. burgdorferi proteins were separated by two-dimensional gel electrophoresis, and the results revealed that six proteins of the wild type were not detected in the ctpA mutant and that nine proteins observed in the ctpA mutant were undetectable in the wild type. Immunoblot analysis showed that the integral outer membrane protein P13 was larger and had a more acidic pI in the ctpA mutant, which is consistent with the theoretical change in pI for P13 not processed at the carboxyl terminus. Matrix-assisted laser desorption ionization-time of flight data indicated that in addition to P13, the BB0323 protein may serve as a substrate for carboxyl-terminal processing by CtpA. Complementation analysis of the ctpA mutant provided strong evidence that the observed effect on proteins depended on inactivation of the ctpA gene alone. We show that CtpA in B. burgdorferi is involved in the processing of proteins such as P13 and BB0323 and that inactivation of ctpA has a pleiotropic effect on borrelial protein synthesis. To our knowledge, this is the first analysis of both a CtpA protease and different substrate proteins in a pathogenic bacterium.
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Affiliation(s)
- Yngve Ostberg
- Department of Molecular Biology, Umeå University, SE-901 87 Umeå, Sweden
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Berks BC, Palmer T, Sargent F. The Tat protein translocation pathway and its role in microbial physiology. Adv Microb Physiol 2003; 47:187-254. [PMID: 14560665 DOI: 10.1016/s0065-2911(03)47004-5] [Citation(s) in RCA: 193] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Tat (twin arginine translocation) protein transport system functions to export folded protein substrates across the bacterial cytoplasmic membrane and to insert certain integral membrane proteins into that membrane. It is entirely distinct from the Sec pathway. Here, we describe our current knowledge of the molecular features of the Tat transport system. In addition, we discuss the roles that the Tat pathway plays in the bacterial cell, paying particular attention to the involvement of the Tat pathway in the biogenesis of cofactor-containing proteins, in cell wall biosynthesis and in bacterial pathogenicity.
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Affiliation(s)
- Ben C Berks
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
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21
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ElAntak L, Morelli X, Bornet O, Hatchikian C, Czjzek M, Dolla A, Guerlesquin F. The cytochrome c3-[Fe]-hydrogenase electron-transfer complex: structural model by NMR restrained docking. FEBS Lett 2003; 548:1-4. [PMID: 12885397 DOI: 10.1016/s0014-5793(03)00718-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Cytochrome c(3) (M(r) 13000) is a low redox potential cytochrome specific of the anaerobic metabolism in sulfate-reducing bacteria. This tetrahemic cytochrome is an intermediate between the [Fe]-hydrogenase and the cytochrome Hmc in Desulfovibrio vulgaris Hildenborough strain. The present work describes the structural model of the cytochrome c(3)-[Fe]-hydrogenase complex obtained by nuclear magnetic resonance restrained docking. This model connects the distal cluster of the [Fe]-hydrogenase to heme 4 of the cytochrome, the same heme found in the interaction with cytochrome Hmc. This result gives evidence that cytochrome c(3) is an electron shuttle between the periplasmic hydrogenase and the Hmc membrane-bound complex.
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Affiliation(s)
- Latifa ElAntak
- Unité de Bioénergétique et Ingénierie des Protéines, IBSM-CNRS, 31 chemin Joseph Aiguier, 13402 Cedex 20, Marseille, France.
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22
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Abstract
Hydrogenases are enzymes capable of catalyzing the oxidation of molecular hydrogen or its production from protons and electrons according to the reversible reaction: H(2)<==>2H(+)+2e(-). Most of these enzymes fall into to major classes: NiFe and Fe-only hydrogenases. Extensive spectroscopic, electrochemical and structural studies have shed appreciable light on the catalytic mechanism of hydrogenases. Although evolutionarily unrelated, NiFe and Fe-hydrogenases share a common, unusual feature: an active site low-spin Fe center with CO and CN coordination. We have recently focused our attention on Fe-hydrogenases because from structural studies by us and others, it appears to be a simpler system than the NiFe counterpart. Thus the primary hydrogen binding site has been identified and plausible, electron, proton and hydrogen pathways from and to the buried active site may be proposed from the structural data. The extensive genome sequencing effort currently under way has shown that eukaryotic organisms contain putatively gene coding sequences that display significant homology to Fe-hydrogenases. Here, we summarize the available evidence concerning the mechanism of these enzymes and carry out a structural comparison between Fe-hydrogenases and related proteins of unknown metal content from yeast, plant, worm, insect and mammals.
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Affiliation(s)
- Yvain Nicolet
- Laboratoire de Cristallographie et de Cristallogenèse des Protéines, Institut de Biologie Structurale Jean-Pierre Ebel, CEA, CNRS, UJF, 41, rue Jules Horowitz, 38027 Grenoble, Cedex 1, France
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Noppa L, Ostberg Y, Lavrinovicha M, Bergström S. P13, an integral membrane protein of Borrelia burgdorferi, is C-terminally processed and contains surface-exposed domains. Infect Immun 2001; 69:3323-34. [PMID: 11292755 PMCID: PMC98291 DOI: 10.1128/iai.69.5.3323-3334.2001] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2000] [Accepted: 01/25/2001] [Indexed: 11/20/2022] Open
Abstract
To elucidate antigens present on the bacterial surface of Borrelia burgdorferi sensu lato that may be involved in pathogenesis, we characterized a protein, P13, with an apparent molecular mass of 13 kDa. The protein was immunogenic and was expressed in large amounts during in vitro cultivation compared to other known antigens. An immunofluorescence assay, immunoelectron microscopy, and protease sensitivity assays indicated that P13 is surface exposed. The deduced sequence of the P13 peptide revealed a possible signal peptidase type I cleavage site, and computer analysis predicted that P13 is an integral membrane protein with three transmembrane-spanning domains. Mass spectrometry, in vitro translation, and N- and C-terminal amino acid sequencing analyses indicated that P13 was posttranslationally processed at both ends and modified by an unknown mechanism. Furthermore, p13 belongs to a gene family with five additional members in B. burgdorferi sensu stricto. The p13 gene is located on the linear chromosome of the bacterium, in contrast to five paralogous genes, which are located on extrachromosomal plasmids. The size of the p13 transcript was consistent with a monocistronic transcript. This new gene family may be involved in functions that are specific for this spirochete and its pathogenesis.
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Affiliation(s)
- L Noppa
- Department of Microbiology, Umeå University, SE-901 87 Umeå, Sweden
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Morelli X, Czjzek M, Hatchikian CE, Bornet O, Fontecilla-Camps JC, Palma NP, Moura JJ, Guerlesquin F. Structural model of the Fe-hydrogenase/cytochrome c553 complex combining transverse relaxation-optimized spectroscopy experiments and soft docking calculations. J Biol Chem 2000; 275:23204-10. [PMID: 10748163 DOI: 10.1074/jbc.m909835199] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Fe-hydrogenase is a 54-kDa iron-sulfur enzyme essential for hydrogen cycling in sulfate-reducing bacteria. The x-ray structure of Desulfovibrio desulfuricans Fe-hydrogenase has recently been solved, but structural information on the recognition of its redox partners is essential to understand the structure-function relationships of the enzyme. In the present work, we have obtained a structural model of the complex of Fe-hydrogenase with its redox partner, the cytochrome c(553), combining docking calculations and NMR experiments. The putative models of the complex demonstrate that the small subunit of the hydrogenase has an important role in the complex formation with the redox partner; 50% of the interacting site on the hydrogenase involves the small subunit. The closest contact between the redox centers is observed between Cys-38, a ligand of the distal cluster of the hydrogenase and Cys-10, a ligand of the heme in the cytochrome. The electron pathway from the distal cluster of the Fe-hydrogenase to the heme of cytochrome c(553) was investigated using the software Greenpath and indicates that the observed cysteine/cysteine contact has an essential role. The spatial arrangement of the residues on the interface of the complex is very similar to that already described in the ferredoxin-cytochrome c(553) complex, which therefore, is a very good model for the interacting domain of the Fe-hydrogenase-cytochrome c(553).
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Affiliation(s)
- X Morelli
- Unité de Bioénergétique et Ingénierie des Protéines, IBSM-CNRS, Marseille Cedex 20, France
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Abstract
Many microorganisms can use molecular hydrogen as a source of electrons or generate it by reducing protons. These reactions are catalysed by metalloenzymes of two types: NiFe and Fe-only hydrogenases. Here, we review recent structural results concerning the latter, putting special emphasis on the characteristics of the active site.
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Affiliation(s)
- Y Nicolet
- Laboratoire de Cristallographie et de Cristallogenèse des Protéines, Institut de Biologie Structurale Jean-Pierre Ebel, CEA-CNRS, 41 Avenue des Martyrs, 38027, Grenoble Cedex 1, France
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26
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Abstract
The Tat (twin-arginine translocation) system is a bacterial protein export pathway with the remarkable ability to transport folded proteins across the cytoplasmic membrane. Preproteins are directed to the Tat pathway by signal peptides that bear a characteristic sequence motif, which includes consecutive arginine residues. Here, we review recent progress on the characterization of the Tat system and critically discuss the structure and operation of this major new bacterial protein export pathway.
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Affiliation(s)
- B C Berks
- Centre for Metalloprotein Spectroscopy and Biology, School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
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