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Bährle R, Böhnke S, Englhard J, Bachmann J, Perner M. Current status of carbon monoxide dehydrogenases (CODH) and their potential for electrochemical applications. BIORESOUR BIOPROCESS 2023; 10:84. [PMID: 38647803 PMCID: PMC10992861 DOI: 10.1186/s40643-023-00705-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 11/16/2023] [Indexed: 04/25/2024] Open
Abstract
Anthropogenic carbon dioxide (CO2) levels are rising to alarming concentrations in earth's atmosphere, causing adverse effects and global climate changes. In the last century, innovative research on CO2 reduction using chemical, photochemical, electrochemical and enzymatic approaches has been addressed. In particular, natural CO2 conversion serves as a model for many processes and extensive studies on microbes and enzymes regarding redox reactions involving CO2 have already been conducted. In this review we focus on the enzymatic conversion of CO2 to carbon monoxide (CO) as the chemical conversion downstream of CO production render CO particularly attractive as a key intermediate. We briefly discuss the different currently known natural autotrophic CO2 fixation pathways, focusing on the reversible reaction of CO2, two electrons and protons to CO and water, catalyzed by carbon monoxide dehydrogenases (CODHs). We then move on to classify the different type of CODHs, involved catalyzed chemical reactions and coupled metabolisms. Finally, we discuss applications of CODH enzymes in photochemical and electrochemical cells to harness CO2 from the environment transforming it into commodity chemicals.
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Affiliation(s)
- Rebecca Bährle
- Department of Marine Geomicrobiology, Faculty of Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148, Kiel, Germany
| | - Stefanie Böhnke
- Department of Marine Geomicrobiology, Faculty of Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148, Kiel, Germany
| | - Jonas Englhard
- Chemistry of Thin Film Materials, IZNF, Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstr. 3, 91058, Erlangen, Germany
| | - Julien Bachmann
- Chemistry of Thin Film Materials, IZNF, Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstr. 3, 91058, Erlangen, Germany
| | - Mirjam Perner
- Department of Marine Geomicrobiology, Faculty of Marine Biogeochemistry, GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148, Kiel, Germany.
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2
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Hay Mele B, Monticelli M, Leone S, Bastoni D, Barosa B, Cascone M, Migliaccio F, Montemagno F, Ricciardelli A, Tonietti L, Rotundi A, Cordone A, Giovannelli D. Oxidoreductases and metal cofactors in the functioning of the earth. Essays Biochem 2023; 67:653-670. [PMID: 37503682 PMCID: PMC10423856 DOI: 10.1042/ebc20230012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2023] [Revised: 07/03/2023] [Accepted: 07/10/2023] [Indexed: 07/29/2023]
Abstract
Life sustains itself using energy generated by thermodynamic disequilibria, commonly existing as redox disequilibria. Metals are significant players in controlling redox reactions, as they are essential components of the engine that life uses to tap into the thermodynamic disequilibria necessary for metabolism. The number of proteins that evolved to catalyze redox reactions is extraordinary, as is the diversification level of metal cofactors and catalytic domain structures involved. Notwithstanding the importance of the topic, the relationship between metals and the redox reactions they are involved in has been poorly explored. This work reviews the structure and function of different prokaryotic organometallic-protein complexes, highlighting their pivotal role in controlling biogeochemistry. We focus on a specific subset of metal-containing oxidoreductases (EC1 or EC7.1), which are directly involved in biogeochemical cycles, i.e., at least one substrate or product is a small inorganic molecule that is or can be exchanged with the environment. Based on these inclusion criteria, we select and report 59 metalloenzymes, describing the organometallic structure of their active sites, the redox reactions in which they are involved, and their biogeochemical roles.
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Affiliation(s)
- Bruno Hay Mele
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Maria Monticelli
- Department of Biology, University of Naples Federico II, Naples, Italy
- National Research Council - Institute of Biomolecular Chemistry - CNR-ICB, Pozzuoli, Italy
| | - Serena Leone
- Dipartimento di Biologia ed Evoluzione degli Organismi Marini, Stazione Zoologica Anton. Dohrn, Napoli, Italy
| | - Deborah Bastoni
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Bernardo Barosa
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Martina Cascone
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Flavia Migliaccio
- Department of Biology, University of Naples Federico II, Naples, Italy
| | | | | | - Luca Tonietti
- Department of Biology, University of Naples Federico II, Naples, Italy
- Department of Science and Technology, University of Naples Parthenope, Naples, Italy
| | - Alessandra Rotundi
- Department of Science and Technology, University of Naples Parthenope, Naples, Italy
| | - Angelina Cordone
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Donato Giovannelli
- Department of Biology, University of Naples Federico II, Naples, Italy
- Department of Science and Technology, University of Naples Parthenope, Naples, Italy
- National Research Council - Institute of Marine Biological Resources and Biotechnologies - CNR-IRBIM, Ancona, Italy
- Department of Marine and Coastal Science, Rutgers University, New Brunswick, NJ, U.S.A
- Marine Chemistry and Geochemistry Department - Woods Hole Oceanographic Institution, MA, U.S.A
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
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3
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Kirk ML, Hille R. Spectroscopic Studies of Mononuclear Molybdenum Enzyme Centers. Molecules 2022; 27:4802. [PMID: 35956757 PMCID: PMC9370002 DOI: 10.3390/molecules27154802] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 06/26/2022] [Accepted: 06/29/2022] [Indexed: 02/06/2023] Open
Abstract
A concise review is provided of the contributions that various spectroscopic methods have made to our understanding of the physical and electronic structures of mononuclear molybdenum enzymes. Contributions to our understanding of the structure and function of each of the major families of these enzymes is considered, providing a perspective on how spectroscopy has impacted the field.
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Affiliation(s)
- Martin L. Kirk
- Department of Chemistry and Chemical Biology, The University of New Mexico, MSC03 2060, 1 University of New Mexico, Albuquerque, NM 87131-0001, USA
| | - Russ Hille
- Department of Biochemistry, Boyce Hall 1463, University of California, Riverside, CA 82521, USA
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4
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Hille R, Niks D. Application of EPR and related methods to molybdenum-containing enzymes. Methods Enzymol 2022; 666:373-412. [PMID: 35465925 DOI: 10.1016/bs.mie.2022.02.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A description is provided of the contributions made to our understanding of molybdenum-containing enzymes through the application of electron paramagnetic resonance spectroscopy and related methods, by way of illustrating how these can be applied to better understand enzyme structure and function. An emphasis is placed on the use of EPR to identify both the coordination environment of the molybdenum coordination sphere as well as the structures of paramagnetic intermediates observed transiently in the course of reaction that have led to the elucidation of reaction mechanism.
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Affiliation(s)
- Russ Hille
- Department of Biochemistry, University of California, Riverside, CA, United States.
| | - Dimitri Niks
- Department of Biochemistry, University of California, Riverside, CA, United States
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5
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Greening C, Grinter R. Microbial oxidation of atmospheric trace gases. Nat Rev Microbiol 2022; 20:513-528. [PMID: 35414013 DOI: 10.1038/s41579-022-00724-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/11/2022] [Indexed: 02/06/2023]
Abstract
The atmosphere has recently been recognized as a major source of energy sustaining life. Diverse aerobic bacteria oxidize the three most abundant reduced trace gases in the atmosphere, namely hydrogen (H2), carbon monoxide (CO) and methane (CH4). This Review describes the taxonomic distribution, physiological role and biochemical basis of microbial oxidation of these atmospheric trace gases, as well as the ecological, environmental, medical and astrobiological importance of this process. Most soil bacteria and some archaea can survive by using atmospheric H2 and CO as alternative energy sources, as illustrated through genetic studies on Mycobacterium cells and Streptomyces spores. Certain specialist bacteria can also grow on air alone, as confirmed by the landmark characterization of Methylocapsa gorgona, which grows by simultaneously consuming atmospheric CH4, H2 and CO. Bacteria use high-affinity lineages of metalloenzymes, namely hydrogenases, CO dehydrogenases and methane monooxygenases, to utilize atmospheric trace gases for aerobic respiration and carbon fixation. More broadly, trace gas oxidizers enhance the biodiversity and resilience of soil and marine ecosystems, drive primary productivity in extreme environments such as Antarctic desert soils and perform critical regulatory services by mitigating anthropogenic emissions of greenhouse gases and toxic pollutants.
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Affiliation(s)
- Chris Greening
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia. .,Securing Antarctica's Environmental Future, Monash University, Clayton, Victoria, Australia. .,Centre to Impact AMR, Monash University, Clayton, Victoria, Australia.
| | - Rhys Grinter
- Department of Microbiology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria, Australia.
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6
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Maiti BK, Maia LB, Moura JJG. Sulfide and transition metals - A partnership for life. J Inorg Biochem 2021; 227:111687. [PMID: 34953313 DOI: 10.1016/j.jinorgbio.2021.111687] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 11/24/2021] [Accepted: 11/28/2021] [Indexed: 12/13/2022]
Abstract
Sulfide and transition metals often came together in Biology. The variety of possible structural combinations enabled living organisms to evolve an array of highly versatile metal-sulfide centers to fulfill different physiological roles. The ubiquitous iron‑sulfur centers, with their structural, redox, and functional diversity, are certainly the best-known partners, but other metal-sulfide centers, involving copper, nickel, molybdenum or tungsten, are equally crucial for Life. This review provides a concise overview of the exclusive sulfide properties as a metal ligand, with emphasis on the structural aspects and biosynthesis. Sulfide as catalyst and as a substrate is discussed. Different enzymes are considered, including xanthine oxidase, formate dehydrogenases, nitrogenases and carbon monoxide dehydrogenases. The sulfide effect on the activity and function of iron‑sulfur, heme and zinc proteins is also addressed.
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Affiliation(s)
- Biplab K Maiti
- National Institute of Technology Sikkim, Department of Chemistry, Ravangla Campus, Barfung Block, Ravangla Sub Division, South Sikkim 737139, India.
| | - Luisa B Maia
- LAQV, REQUIMTE, Department of Chemistry, NOVA School of Science and Technology (FCT NOVA), Universidade NOVA de Lisboa, Campus de Caparica, Portugal.
| | - José J G Moura
- LAQV, REQUIMTE, Department of Chemistry, NOVA School of Science and Technology (FCT NOVA), Universidade NOVA de Lisboa, Campus de Caparica, Portugal.
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7
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Kalimuthu P, Petitgenet M, Niks D, Dingwall S, Harmer JR, Hille R, Bernhardt PV. The oxidation-reduction and electrocatalytic properties of CO dehydrogenase from Oligotropha carboxidovorans. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2019; 1861:148118. [PMID: 31734195 DOI: 10.1016/j.bbabio.2019.148118] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 10/19/2019] [Accepted: 11/04/2019] [Indexed: 01/25/2023]
Abstract
CO dehydrogenase (CODH) from the Gram-negative bacterium Oligotropha carboxidovorans is a complex metalloenzyme from the xanthine oxidase family of molybdenum-containing enzymes, bearing a unique binuclear Mo-S-Cu active site in addition to two [2Fe-2S] clusters (FeSI and FeSII) and one equivalent of FAD. CODH catalyzes the oxidation of CO to CO2 with the concomitant introduction of reducing equivalents into the quinone pool, thus enabling the organism to utilize CO as sole source of both carbon and energy. Using a variety of EPR monitored redox titrations and spectroelectrochemistry, we report the redox potentials of CO dehydrogenase at pH 7.2 namely MoVI/V, MoV/IV, FeSI2+/+, FeSII2+/+, FAD/FADH and FADH/FADH-. These potentials are systematically higher than the corresponding potentials seen for other members of the xanthine oxidase family of Mo enzymes, and are in line with CODH utilising the higher potential quinone pool as an electron acceptor instead of pyridine nucleotides. CODH is also active when immobilised on a modified Au working electrode as demonstrated by cyclic voltammetry in the presence of CO.
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Affiliation(s)
- Palraj Kalimuthu
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane 4072, Australia
| | - Mélanie Petitgenet
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane 4072, Australia
| | - Dimitri Niks
- Department of Biochemistry, University of California, Riverside, CA 92521, USA
| | - Stephanie Dingwall
- Department of Biochemistry, University of California, Riverside, CA 92521, USA
| | - Jeffrey R Harmer
- Centre for Advanced Imaging, University of Queensland, Brisbane 4072, Australia
| | - Russ Hille
- Department of Biochemistry, University of California, Riverside, CA 92521, USA
| | - Paul V Bernhardt
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane 4072, Australia.
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8
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Abstract
Carbon monoxide dehydrogenases (CODHs) catalyze the reversible oxidation of CO with water to CO2, two electrons, and two protons. Two classes of CODHs exist, having evolved from different scaffolds featuring active sites built from different transition metals. The basic properties of both classes are described in this overview chapter.
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Affiliation(s)
- Jae-Hun Jeoung
- Institute of Biology, Structural Biology and Biochemistry, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Berta M Martins
- Institute of Biology, Structural Biology and Biochemistry, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Holger Dobbek
- Institute of Biology, Structural Biology and Biochemistry, Humboldt-Universität zu Berlin, Berlin, Germany.
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9
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Molybdenum-Containing Enzymes. Methods Mol Biol 2018. [PMID: 30317474 DOI: 10.1007/978-1-4939-8864-8_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
An overview of modern methods used in the preparation and characterization of molybdenum-containing enzymes is presented, with an emphasis on those methods that have been developed over the past decade to address specific difficulties frequently encountered in studies of these enzymes.
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11
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Kaufmann P, Duffus BR, Teutloff C, Leimkühler S. Functional Studies on Oligotropha carboxidovorans Molybdenum–Copper CO Dehydrogenase Produced in Escherichia coli. Biochemistry 2018; 57:2889-2901. [DOI: 10.1021/acs.biochem.8b00128] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Paul Kaufmann
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, 14476 Potsdam, Germany
| | - Benjamin R. Duffus
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, 14476 Potsdam, Germany
| | - Christian Teutloff
- Institute for Experimental Physics, Free University of Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Silke Leimkühler
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, 14476 Potsdam, Germany
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12
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Gourlay C, Nielsen DJ, Evans DJ, White JM, Young CG. Models for aerobic carbon monoxide dehydrogenase: synthesis, characterization and reactivity of paramagnetic Mo VO(μ-S)Cu I complexes. Chem Sci 2018; 9:876-888. [PMID: 29629154 PMCID: PMC5873225 DOI: 10.1039/c7sc04239f] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 11/18/2017] [Indexed: 12/02/2022] Open
Abstract
Complexes exhibiting the MoVO(μ-S)CuI cores, EPR properties, electronic structures and biomimetic reactions of aerobic Mo/Cu-containing carbon monoxide dehydrogenases are reported.
Reaction of [CoCp2][TpiPrMoOS(OAr)] [Cp = η5-cyclopentadienyl; TpiPr = hydrotris(3-isopropylpyrazol-1-yl)borate; OAr = phenolate or derivative thereof] with [Cu(NCMe)(Me3tcn)]BF4 (Me3tcn = 1,4,7-trimethyl-1,4,7-triazacyclononane) in MeCN at –30 °C results in the formation of red-brown/black, paramagnetic, μ-sulfido-Mo(v)/Cu(i) complexes, TpiPrMoO(OAr)(μ-S)Cu(Me3tcn). The complexes possess the MoO(μ-S)Cu core found in aerobic carbon monoxide dehydrogenases (CODHs) and exhibit X-band EPR spectra closely related to those of semi-reduced CODH, with giso ∼ 1.937, hyperfine coupling to 95,97Mo (aiso = 39–42 × 10–4 cm–1) and strong superhyperfine coupling to 63,65Cu (aiso = 34–63 × 10–4 cm–1). Anisotropic spectra exhibit monoclinic symmetry with g1 ∼ 1.996, g2 ∼ 1.944 and g3 ∼ 1.882, and nearly isotropic ACu values (75–90 × 10–4 cm–1). The X-ray structures of four derivatives (Ar = Ph, C6H4tBu-2, C6H4sBu-2, C6H4Ph-4) are reported and discussed along with that of the Ar = C6H3tBu2-3,5 derivative (communicated in C. Gourlay, D. J. Nielsen, J. M. White, S. Z. Knottenbelt, M. L. Kirk and C. G. Young, J. Am. Chem. Soc., 2006, 128, 2164). The complexes exhibit distorted octahedral oxo-Mo(v) and distorted tetrahedral Cu(i) centres bridged by a single bent μ-sulfido ligand, with Mo–S and Cu–S distances and Mo–S–Cu angles in the ranges 2.262–2.300 Å, 2.111–2.134 Å and 115.87–134.27°, respectively. The 2 t-butyl derivative adopts a unique phenolate conformation with O
Created by potrace 1.16, written by Peter Selinger 2001-2019
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Mo–O–Cα and O
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Mo–S–Cu torsion angles of 92.7 and 21.1°, respectively, very different from those of the other structurally characterized derivatives (31–47 and 33–45°, respectively) and exhibits a relatively short Mo···Cu distance [3.752(2) Å vs. 3.806(7)–4.040(2) Å]. As well, the aCu value of this complex (34.3 × 10–4 cm–1) is much lower than the values observed for other members of the series (55–63 × 10–4 cm–1), supporting the hypothesis that the electronic structure of the MoO(μ-S)Cu core unit and the degree of intermetallic communication are strongly dependent on the geometry of the MoO(OR)(μ-S)Cu unit. The complexes participate in an electrochemically reversible Mo(vi)/Mo(v) redox couple and react with cyanide undergoing decupration and desulfurization reactions of the type observed for CODH.
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Affiliation(s)
- Craig Gourlay
- School of Chemistry , University of Melbourne , Victoria 3010 , Australia
| | - David J Nielsen
- School of Chemistry , University of Melbourne , Victoria 3010 , Australia
| | - David J Evans
- School of Chemistry , University of Melbourne , Victoria 3010 , Australia
| | - Jonathan M White
- School of Chemistry , University of Melbourne , Victoria 3010 , Australia.,Bio21 Molecular Science and Biotechnology Institute , University of Melbourne , Victoria 3010 , Australia
| | - Charles G Young
- Department of Chemistry and Physics , La Trobe Institute for Molecular Science , La Trobe University , Melbourne , Victoria 3086 , Australia .
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Maia LB, Moura I, Moura JJ. EPR Spectroscopy on Mononuclear Molybdenum-Containing Enzymes. FUTURE DIRECTIONS IN METALLOPROTEIN AND METALLOENZYME RESEARCH 2017. [DOI: 10.1007/978-3-319-59100-1_4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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14
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Dingwall S, Wilcoxen J, Niks D, Hille R. Studies of carbon monoxide dehydrogenase from Oligotropha carboxidovorans. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.molcatb.2016.10.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Pelzmann AM, Mickoleit F, Meyer O. Insights into the posttranslational assembly of the Mo-, S- and Cu-containing cluster in the active site of CO dehydrogenase of Oligotropha carboxidovorans. J Biol Inorg Chem 2014; 19:1399-414. [PMID: 25377894 PMCID: PMC4240915 DOI: 10.1007/s00775-014-1201-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 09/30/2014] [Indexed: 12/13/2022]
Abstract
Oligotropha carboxidovorans is characterized by the aerobic chemolithoautotrophic utilization of CO. CO oxidation by CO dehydrogenase proceeds at a unique bimetallic [CuSMoO2] cluster which matures posttranslationally while integrated into the completely folded apoenzyme. Kanamycin insertional mutants in coxE, coxF and coxG were characterized with respect to growth, expression of CO dehydrogenase, and the type of metal center present. These data along with sequence information were taken to delineate a model of metal cluster assembly. Biosynthesis starts with the MgATP-dependent, reductive sulfuration of [Mo(VI)O3] to [Mo(V)O2SH] which entails the AAA+-ATPase chaperone CoxD. Then Mo(V) is reoxidized and Cu(1+)-ion is integrated. Copper is supplied by the soluble CoxF protein which forms a complex with the membrane-bound von Willebrand protein CoxE through RGD-integrin interactions and enables the reduction of CoxF-bound Cu(2+), employing electrons from respiration. Copper appears as Cu(2+)-phytate, is mobilized through the phytase activity of CoxF and then transferred to the CoxF putative copper-binding site. The coxG gene does not participate in the maturation of the bimetallic cluster. Mutants in coxG retained the ability to utilize CO, although at a lower growth rate. They contained a regular CO dehydrogenase with a functional catalytic site. The presence of a pleckstrin homology (PH) domain on CoxG and the observed growth rates suggest a role of the PH domain in recruiting CO dehydrogenase to the cytoplasmic membrane enabling electron transfer from the enzyme to the respiratory chain. CoxD, CoxE and CoxF combine motifs of a DEAD-box RNA helicase which would explain their mutual translation.
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Affiliation(s)
- Astrid M. Pelzmann
- Department of Microbiology, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
| | - Frank Mickoleit
- Department of Microbiology, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
| | - Ortwin Meyer
- Department of Microbiology, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
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16
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Zanello P. The competition between chemistry and biology in assembling iron–sulfur derivatives. Molecular structures and electrochemistry. Part II. {[Fe2S2](SγCys)4} proteins. Coord Chem Rev 2014. [DOI: 10.1016/j.ccr.2014.08.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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17
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The aerobic CO dehydrogenase from Oligotropha carboxidovorans. J Biol Inorg Chem 2014; 20:243-51. [PMID: 25156151 DOI: 10.1007/s00775-014-1188-4] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 08/13/2014] [Indexed: 10/24/2022]
Abstract
We review here the recent literature dealing with the molybdenum- and copper-dependent CO dehydrogenase, with particular emphasis on the structure of the enzyme and recent advances in our understanding of the reaction mechanism of the enzyme.
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18
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Affiliation(s)
- Russ Hille
- Department of Biochemistry, University of California, Riverside, Riverside, California 92521, United States
| | - James Hall
- Department of Biochemistry, University of California, Riverside, Riverside, California 92521, United States
| | - Partha Basu
- Department of Chemistry and Biochemistry, Duquesne University, Pittsburgh, Pennsylvania 15282, United States
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19
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Shanmugam M, Wilcoxen J, Habel-Rodriguez D, Cutsail GE, Kirk ML, Hoffman BM, Hille R. (13)C and (63,65)Cu ENDOR studies of CO dehydrogenase from Oligotropha carboxidovorans. Experimental evidence in support of a copper-carbonyl intermediate. J Am Chem Soc 2013; 135:17775-82. [PMID: 24147852 DOI: 10.1021/ja406136f] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report here an ENDOR study of an S = 1/2 intermediate state trapped during reduction of the binuclear Mo/Cu enzyme CO dehydrogenase by CO. ENDOR spectra of this state confirm that the (63,65)Cu nuclei exhibits strong and almost entirely isotropic coupling to the unpaired electron, show that this coupling atypically has a positive sign, aiso = +148 MHz, and indicate an apparently undetectably small quadrupolar coupling. When the intermediate is generated using (13)CO, coupling to the (13)C is observed, with aiso = +17.3 MHz. A comparison with the couplings seen in related, structurally assigned Mo(V) species from xanthine oxidase, in conjunction with complementary computational studies, leads us to conclude that the intermediate contains a partially reduced Mo(V)/Cu(I) center with CO bound at the copper. Our results provide strong experimental support for a reaction mechanism that proceeds from a comparable complex of CO with fully oxidized Mo(VI)/Cu(I) enzyme.
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Affiliation(s)
- Muralidharan Shanmugam
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208-3113, United States
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Wilcoxen J, Hille R. The hydrogenase activity of the molybdenum/copper-containing carbon monoxide dehydrogenase of Oligotropha carboxidovorans. J Biol Chem 2013; 288:36052-60. [PMID: 24165123 DOI: 10.1074/jbc.m113.522441] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The reaction of the air-tolerant CO dehydrogenase from Oligotropha carboxidovorans with H2 has been examined. Like the Ni-Fe CO dehydrogenase, the enzyme can be reduced by H2 with a limiting rate constant of 5.3 s(-1) and a dissociation constant Kd of 525 μM; both kred and kred/Kd, reflecting the breakdown of the Michaelis complex and the reaction of free enzyme with free substrate in the low [S] regime, respectively, are largely pH-independent. During the reaction with H2, a new EPR signal arising from the Mo/Cu-containing active site of the enzyme is observed which is distinct from the signal seen when the enzyme is reduced by CO, with greater g anisotropy and larger hyperfine coupling to the active site (63,65)Cu. The signal also exhibits hyperfine coupling to at least two solvent-exchangeable protons of bound substrate that are rapidly exchanged with solvent. Proton coupling is also evident in the EPR signal seen with the dithionite-reduced native enzyme, and this coupling is lost in the presence of bicarbonate. We attribute the coupled protons in the dithionite-reduced enzyme to coordinated water at the copper site in the native enzyme and conclude that bicarbonate is able to displace this water from the copper coordination sphere. On the basis of our results, a mechanism for H2 oxidation is proposed which involves initial binding of H2 to the copper of the binuclear center, displacing the bound water, followed by sequential deprotonation through a copper-hydride intermediate to reduce the binuclear center.
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Affiliation(s)
- Jarett Wilcoxen
- From the Department of Biochemistry, University of California, Riverside, California 92521
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21
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Maisel T, Joseph S, Mielke T, Bürger J, Schwarzinger S, Meyer O. The CoxD protein, a novel AAA+ ATPase involved in metal cluster assembly: hydrolysis of nucleotide-triphosphates and oligomerization. PLoS One 2012; 7:e47424. [PMID: 23077613 PMCID: PMC3471820 DOI: 10.1371/journal.pone.0047424] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 09/17/2012] [Indexed: 11/18/2022] Open
Abstract
CoxD of the α-proteobacterium Oligotropha carboxidovorans is a membrane protein which is involved in the posttranslational biosynthesis of the [CuSMoO₂] cluster in the active site of the enzyme CO dehydrogenase. The bacteria synthesize CoxD only in the presence of CO. Recombinant CoxD produced in E. coli K38 pGP1-2/pETMW2 appeared in inclusion bodies from where it was solubilized by urea and refolded by stepwise dilution. Circular dichroism spectroscopy revealed the presence of secondary structural elements in refolded CoxD. CoxD is a P-loop ATPase of the AAA-protein family. Refolded CoxD catalyzed the hydrolysis of MgATP yielding MgADP and inorganic phosphate at a 1∶1∶1 molar ratio. The reaction was inhibited by the slow hydrolysable MgATP-γ-S. GTPase activity of CoxD did not exceed 2% of the ATPase activity. Employing different methods (non linear regression, Hanes and Woolf, Lineweaver-Burk), preparations of CoxD revealed a mean K(M) value of 0.69±0.14 mM ATP and an apparent V(max) value of 19.3±2.3 nmol ATP hydrolyzed min⁻¹ mg⁻¹. Sucrose density gradient centrifugation and gel filtration showed that refolded CoxD can exist in various multimeric states (2-mer, 4-mer or 6-mer), preferentially as hexamer or dimer. Within weeks the hexamer dissociates into the dimer, a process which can be reversed by MgATP or MgATP-γ-S within hours. Only the hexamers and the dimers exhibited MgATPase activity. Transmission electron microscopy of negatively stained CoxD preparations revealed distinct particles within a size range of 10-16 nm, which further corroborates the oligomeric organization. The 3D structure of CoxD was modeled with the 3D structure of BchI from Rhodobacter capsulatus as template. It has the key elements of an AAA+ domain in the same arrangement and at same positions as in BchI and displays the characteristic inserts of the PS-II-insert clade. Possible functions of CoxD in [CuSMoO₂] cluster assembly are discussed.
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Affiliation(s)
- Tobias Maisel
- Chair of Microbiology, University of Bayreuth, Bayreuth, Germany
| | - Stephanie Joseph
- Chair of Microbiology, University of Bayreuth, Bayreuth, Germany
| | - Thorsten Mielke
- Max-Planck-Institute for Molecular Genetics, Berlin, Germany
- Charité-Universitätsmedizin Berlin, Institute of Medical Physics and Biophysics, Berlin, Germany
| | - Jörg Bürger
- Max-Planck-Institute for Molecular Genetics, Berlin, Germany
- Charité-Universitätsmedizin Berlin, Institute of Medical Physics and Biophysics, Berlin, Germany
| | - Stephan Schwarzinger
- Chair of Biopolymers, University of Bayreuth, Bayreuth, Germany
- The Bayreuth Research Center for Bio-Macromolecules, Bayreuth, Germany
| | - Ortwin Meyer
- Chair of Microbiology, University of Bayreuth, Bayreuth, Germany
- The Bayreuth Research Center for Bio-Macromolecules, Bayreuth, Germany
- * E-mail:
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Wilcoxen J, Snider S, Hille R. Substitution of Silver for Copper in the Binuclear Mo/Cu Center of Carbon Monoxide Dehydrogenase from Oligotropha carboxidovorans. J Am Chem Soc 2011; 133:12934-6. [DOI: 10.1021/ja205073j] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jarett Wilcoxen
- Department of Biochemistry, 1462 Boyce Hall, University of California, Riverside, California 92521, United States
| | - Samantha Snider
- Department of Biochemistry, 1462 Boyce Hall, University of California, Riverside, California 92521, United States
| | - Russ Hille
- Department of Biochemistry, 1462 Boyce Hall, University of California, Riverside, California 92521, United States
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Bender G, Pierce E, Hill JA, Darty JE, Ragsdale SW. Metal centers in the anaerobic microbial metabolism of CO and CO2. Metallomics 2011; 3:797-815. [PMID: 21647480 PMCID: PMC3964926 DOI: 10.1039/c1mt00042j] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Carbon dioxide and carbon monoxide are important components of the carbon cycle. Major research efforts are underway to develop better technologies to utilize the abundant greenhouse gas, CO(2), for harnessing 'green' energy and producing biofuels. One strategy is to convert CO(2) into CO, which has been valued for many years as a synthetic feedstock for major industrial processes. Living organisms are masters of CO(2) and CO chemistry and, here, we review the elegant ways that metalloenzymes catalyze reactions involving these simple compounds. After describing the chemical and physical properties of CO and CO(2), we shift focus to the enzymes and the metal clusters in their active sites that catalyze transformations of these two molecules. We cover how the metal centers on CO dehydrogenase catalyze the interconversion of CO and CO(2) and how pyruvate oxidoreductase, which contains thiamin pyrophosphate and multiple Fe(4)S(4) clusters, catalyzes the addition and elimination of CO(2) during intermediary metabolism. We also describe how the nickel center at the active site of acetyl-CoA synthase utilizes CO to generate the central metabolite, acetyl-CoA, as part of the Wood-Ljungdahl pathway, and how CO is channelled from the CO dehydrogenase to the acetyl-CoA synthase active site. We cover how the corrinoid iron-sulfur protein interacts with acetyl-CoA synthase. This protein uses vitamin B(12) and a Fe(4)S(4) cluster to catalyze a key methyltransferase reaction involving an organometallic methyl-Co(3+) intermediate. Studies of CO and CO(2) enzymology are of practical significance, and offer fundamental insights into important biochemical reactions involving metallocenters that act as nucleophiles to form organometallic intermediates and catalyze C-C and C-S bond formations.
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Affiliation(s)
- Güneş Bender
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-0606, USA. Fax: +1 734-763-4581; Tel: +1 734-615-4621
| | - Elizabeth Pierce
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-0606, USA. Fax: +1 734-763-4581; Tel: +1 734-615-4621
| | - Jeffrey A. Hill
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-0606, USA. Fax: +1 734-763-4581; Tel: +1 734-615-4621
| | - Joseph E. Darty
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-0606, USA. Fax: +1 734-763-4581; Tel: +1 734-615-4621
| | - Stephen W. Ragsdale
- Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan 48109-0606, USA. Fax: +1 734-763-4581; Tel: +1 734-615-4621
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Magalon A, Fedor JG, Walburger A, Weiner JH. Molybdenum enzymes in bacteria and their maturation. Coord Chem Rev 2011. [DOI: 10.1016/j.ccr.2010.12.031] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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25
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Wilcoxen J, Zhang B, Hille R. Reaction of the molybdenum- and copper-containing carbon monoxide dehydrogenase from Oligotropha carboxydovorans with quinones. Biochemistry 2011; 50:1910-6. [PMID: 21275368 DOI: 10.1021/bi1017182] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Carbon monoxide dehydrogenase (CODH) from Oligotropha carboxydovorans catalyzes the oxidation of carbon monoxide to carbon dioxide, providing the organism both a carbon source and energy for growth. In the oxidative half of the catalytic cycle, electrons gained from CO are ultimately passed to the electron transport chain of the Gram-negative organism, but the proximal acceptor of reducing equivalents from the enzyme has not been established. Here we investigate the reaction of the reduced enzyme with various quinones and find them to be catalytically competent. Benzoquinone has a k(ox) of 125.1 s(-1) and a K(d) of 48 μM. Ubiquinone-1 has a k(ox)/K(d) value of 2.88 × 10(5) M(-1) s(-1). 1,4-Naphthoquinone has a k(ox) of 38 s(-1) and a K(d) of 140 μM. 1,2-Naphthoquinone-4-sulfonic acid has a k(ox)/K(d) of 1.31 × 10(5) M(-1) s(-1). An extensive effort to identify a cytochrome that could be reduced by CO/CODH was unsuccessful. Steady-state studies with benzoquinone indicate that the rate-limiting step is in the reductive half of the reaction (that is, the reaction of oxidized enzyme with CO). On the basis of the inhibition of CODH by diphenyliodonium chloride, we conclude that quinone substrates interact with CODH at the enzyme's flavin site. Our results strongly suggest that CODH donates reducing equivalents directly to the quinone pool without using a cytochrome as an intermediary.
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Affiliation(s)
- Jarett Wilcoxen
- Department of Biochemistry, University of California, Riverside, California 92521, United States
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Zhang B, Hemann CF, Hille R. Kinetic and spectroscopic studies of the molybdenum-copper CO dehydrogenase from Oligotropha carboxidovorans. J Biol Chem 2010; 285:12571-8. [PMID: 20178978 DOI: 10.1074/jbc.m109.076851] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Carbon monoxide dehydrogenase from the aerobic bacterium Oligotropha carboxidovorans catalyzes the oxidation of CO to CO(2), yielding two electrons and two H(+). The steady-state kinetics of the enzyme exhibit a pH optimum of 7.2 with a k(cat) of 93.3 s(-1) and K(m) of 10.7 microM at 25 degrees C. k(red) for the reductive half-reaction agrees well with k(cat) and exhibits a similar pH optimum, indicating that the rate-limiting step of overall turnover is likely in the reductive half-reaction. No dependence on CO concentration was observed in the rapid reaction kinetics, however, suggesting that CO initially binds rapidly to the enzyme, possibly at the Cu(I) of the active site, prior to undergoing oxidation. A Mo(V) species that exhibits strong coupling to the copper of the active center (I = 3/2) has been characterized by EPR. The signal is further split when [(13)C]CO is used to generate it, demonstrating that substrate (or product) is a component of the signal-giving species. Finally, resonance Raman spectra of CODH reveal the presence of FAD, Fe/S clusters, and a [CuSMoO(2)] coordination in the active site, consistent with earlier x-ray absorption and crystallographic results.
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Affiliation(s)
- Bo Zhang
- Department of Biochemistry, University of California, Riverside, California 92521, USA
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CO dehydrogenase genes found in metagenomic fosmid clones from the deep mediterranean sea. Appl Environ Microbiol 2009; 75:7436-44. [PMID: 19801465 DOI: 10.1128/aem.01283-09] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The use of carbon monoxide (CO) as a biological energy source is widespread in microbes. In recent years, the role of CO oxidation in superficial ocean waters has been shown to be an important energy supplement for heterotrophs (carboxydovores). The key enzyme CO dehydrogenase was found in both isolates and metagenomes from the ocean's photic zone, where CO is continuously generated by organic matter photolysis. We have also found genes that code for both forms I (low affinity) and II (high affinity) in fosmids from a metagenomic library generated from a 3,000-m depth in the Mediterranean Sea. Analysis of other metagenomic databases indicates that similar genes are also found in the mesopelagic and bathypelagic North Pacific and on the surfaces of this and other oceanic locations (in lower proportions and similarities). The frequency with which this gene was found indicates that this energy-generating metabolism would be at least as important in the bathypelagic habitat as it is in the photic zone. Although there are no data about CO concentrations or origins deep in the ocean, it could have a geothermal origin or be associated with anaerobic metabolism of organic matter. The identities of the microbes that carry out these processes were not established, but they seem to be representatives of either Bacteroidetes or Chloroflexi.
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Pelzmann A, Ferner M, Gnida M, Meyer-Klaucke W, Maisel T, Meyer O. The CoxD protein of Oligotropha carboxidovorans is a predicted AAA+ ATPase chaperone involved in the biogenesis of the CO dehydrogenase [CuSMoO2] cluster. J Biol Chem 2009; 284:9578-86. [PMID: 19189964 DOI: 10.1074/jbc.m805354200] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
CO dehydrogenase from the Gram-negative chemolithoautotrophic eubacterium Oligotropha carboxidovorans OM5 is a structurally characterized molybdenum-containing iron-sulfur flavoenzyme, which catalyzes the oxidation of CO (CO + H(2)O --> CO(2) + 2e(-) + 2H(+)). It accommodates in its active site a unique bimetallic [CuSMoO(2)] cluster, which is subject to post-translational maturation. Insertional mutagenesis of coxD has established its requirement for the assembly of the [CuSMoO(2)] cluster. Disruption of coxD led to a phenotype of the corresponding mutant OM5 D::km with the following characteristics: (i) It was impaired in the utilization of CO, whereas the utilization of H(2) plus CO(2) was not affected; (ii) Under appropriate induction conditions bacteria synthesized a fully assembled apo-CO dehydrogenase, which could not oxidize CO; (iii) Apo-CO dehydrogenase contained a [MoO(3)] site in place of the [CuSMoO(2)] cluster; and (iv) Employing sodium sulfide first and then the Cu(I)-(thiourea)(3) complex, the non-catalytic [MoO(3)] site could be reconstituted in vitro to a [CuSMoO(2)] cluster capable of oxidizing CO. Sequence information suggests that CoxD is a MoxR-like AAA+ ATPase chaperone related to the hexameric, ring-shaped BchI component of Mg(2+)-chelatases. Recombinant CoxD, which appeared in Escherichia coli in inclusion bodies, occurs exclusively in cytoplasmic membranes of O. carboxidovorans grown in the presence of CO, and its occurrence coincided with GTPase activity upon sucrose density gradient centrifugation of cell extracts. The presumed function of CoxD is the partial unfolding of apo-CO dehydrogenase to assist in the stepwise introduction of sulfur and copper in the [MoO(3)] center of the enzyme.
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Affiliation(s)
- Astrid Pelzmann
- University of Bayreuth, Universitätsstrasse 30, Bayreuth 95440, Germany
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Maiti D, Woertink JS, Vance MA, Milligan AE, Sarjeant AAN, Solomon EI, Karlin KD. Copper(I)/S8 Reversible Reactions Leading to an End-On Bound Dicopper(II) Disulfide Complex: Nucleophilic Reactivity and Analogies to Copper−Dioxygen Chemistry. J Am Chem Soc 2007; 129:8882-92. [PMID: 17592845 DOI: 10.1021/ja071968z] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Elemental sulfur (S8) reacts reversibly with the copper(I) complex [(TMPA')CuI](+) (1), where TMPA' is a TMPA (tris(2-pyridylmethyl)amine) analogue with a 6-CH2OCH3 substituent on one pyridyl ligand arm, affording a spectroscopically pure end-on bound disulfido-dicopper(II) complex [{(TMPA')Cu(II)}2(mu-1,2-S2(2-))](2+) (2) {nu(S-S) = 492 cm(-1); nu(Cu-S)sym = 309 cm(-1)}; by contrast, [(TMPA)Cu(I)(CH3CN)](+) (3)/S8 chemistry produces an equilibrium mixture of at least three complexes. The reaction of excess PPh3 with 2 leads to formal "release" of zerovalent sulfur and reduction of copper ion to give the corresponding complex [(TMPA')Cu(I)(PPh3)](+) (11) along with S=PPh3 as products. Dioxygen displaces the disulfur moiety from 2 to produce the end-on Cu2O2 complex, [{(TMPA')Cu(II)}2(mu-1,2-O2(2-)](2+) (9). Addition of the tetradentate ligand TMPA to 2 generates the apparently more thermodynamically stable [{(TMPA)Cu(II)}2(mu-1,2-S2(2-))](2+) (4) and expected mixture of other species. Bubbling 2 with CO leads to the formation of the carbonyl adduct [(TMPA')CuI(CO)](+) (8). Carbonylation/sulfur-release/CO-removal cycles can be repeated several times. Sulfur atom transfer from 2 also occurs in a near quantitative manner when it is treated with 2,6-dimethylphenyl isocyanide (ArNC), leading to the corresponding isothiocyanate (ArNCS) and [(TMPA')Cu(I)(CNAr)](+) (12). Complex 2 readily reacts with PhCH2Br: [{(TMPA')Cu(II)}2(mu-1,2-S(2)(2-)](2+) (2) + 2 PhCH2Br --> [{(TMPA')Cu(II)(Br)}2](2+) (6) + PhCH2SSCH2Ph. The unprecedented substrate reactivity studies reveal that end-on bound mu-1,2-disulfide-dicopper(II) complex 2 provides a nucleophilic S2(2-) moiety, in striking contrast to the electrophilic behavior of a recently described side-on bound mu-eta(2):eta(2)-disulfido-dicopper(II) complex, [{(N3)Cu(II)}(2)(mu-eta(2):eta(2)-S2(2-))](2+) (5) with tridentate N3 ligand. The investigation thus reveals striking analogies of copper/sulfur and copper/dioxygen chemistries, with regard to structure type formation and specific substrate reactivity patterns.
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Affiliation(s)
- Debabrata Maiti
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
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Ha SW, Korbas M, Klepsch M, Meyer-Klaucke W, Meyer O, Svetlitchnyi V. Interaction of potassium cyanide with the [Ni-4Fe-5S] active site cluster of CO dehydrogenase from Carboxydothermus hydrogenoformans. J Biol Chem 2007; 282:10639-46. [PMID: 17277357 DOI: 10.1074/jbc.m610641200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Ni-Fe carbon monoxide (CO) dehydrogenase II (CODHII(Ch)) from the anaerobic CO-utilizing hydrogenogenic bacterium Carboxydothermus hydrogenoformans catalyzes the oxidation of CO, presumably at the Ni-(micro(2)S)-Fe1 subsite of the [Ni-4S-5S] cluster in the active site. The CO oxidation mechanism proposed on the basis of several CODHII(Ch) crystal structures involved the apical binding of CO at the nickel ion and the activation of water at the Fe1 ion of the cluster. To understand how CO interacts with the active site, we have studied the reactivity of the cluster with potassium cyanide and analyzed the resulting type of nickel coordination by x-ray absorption spectroscopy. Cyanide acts as a competitive inhibitor of reduced CODHII(Ch) with respect to the substrate CO and is therefore expected to mimic the substrate. It inhibits the enzyme reversibly, forming a nickel cyanide. In this reaction, one of the four square-planar sulfur ligands of nickel is replaced by the carbon atom of cyanide, suggesting removal of the micro(2)S from the Ni-(micro(2)S)-Fe1 subsite. Upon reactivation of the inhibited enzyme, cyanide is released, and the square-planar coordination of nickel by 4S ligands is recovered, which includes the reformation of the Ni-(micro(2)S)-Fe1 bridge. The results are summarized in a model of the CO oxidation mechanism at the [Ni-4Fe-5S] active site cluster of CODHII(Ch) from C. hydrogenoformans.
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Affiliation(s)
- Seung-Wook Ha
- Lehrstuhl für Mikrobiologie and Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, Universitätsstrasse 30, D-95440 Bayreuth, Germany
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Laughlin LJ, Eagle AA, George GN, Tiekink ERT, Young CG. Synthesis, Characterization, and Biomimetic Chemistry of cis-Oxosulfidomolybdenum(VI) Complexes Stabilized by an Intramolecular Mo(O)S···S Interaction. Inorg Chem 2007; 46:939-48. [PMID: 17257038 DOI: 10.1021/ic061213d] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reactions of jade-green Tp*MoIVO(S2PR2) [Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate; R = Et, Pri, Ph] with propylene sulfide produce ochre-red Tp*MoVIOS{SP(S)R2}. The complexes have been characterized by microanalysis, mass spectrometry, cyclic voltammetry, spectroscopy (IR, NMR, UV-vis, and X-ray absorption), and X-ray crystallography. The distorted-octahedral isopropyl and phenyl derivatives feature a tridentate fac-Tp* ligand, a terminal oxo ligand, and a unique five-membered Mo(=S){SP(=S)R2 ring moiety formed by a weak, intramolecular, bonding interaction between the Mo=S1 and (uncoordinated) S3=P moieties. The Mo=S1 [2.227(2) A (R = Pri) and 2.200(2) A (R = Ph)] and S1...S3 distances [2.396(3) A (R = Pri) and 2.383(2) A (R = Ph)] are indicative of a pi-bonded Mo=S1 unit and a weak (bond order ca. 1/3) S1...S3 interaction; the solid-state structures are maintained in solution according to S K-edge X-ray absorption data. The complexes react with excess cyanide to form thiocyanate and Tp*MoO(S2PR2), under anaerobic conditions, or Tp*MoO2(S2PR2), under aerobic conditions; the latter models the production of thiocyanate and desulfo molybdenum hydroxylases upon cyanolysis of molybdenum hydroxylases. The complexes react with triphenylphosphine to give Tp*MoO(S2PR2) and SPPh3, with cobaltocene or hydrosulfide ion to produce [Tp*MoVOS(S2PR2)]-, and with ferrocenium salts to yield [Tp*MoVO(S3PR2)]+; in the last two reactions, Mo(V) is produced by direct or induced internal redox reactions, respectively. The presence of the Mo(O)=S...S interaction does not radically lengthen the Mo=S bond in the complexes or preclude them from reactions typical of unperturbed oxosulfidomolybdenum(VI) complexes.
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Affiliation(s)
- Les J Laughlin
- School of Chemistry, University of Melbourne, Victoria 3010, Australia
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Brondino CD, Romão MJ, Moura I, Moura JJG. Molybdenum and tungsten enzymes: the xanthine oxidase family. Curr Opin Chem Biol 2006; 10:109-14. [PMID: 16480912 DOI: 10.1016/j.cbpa.2006.01.034] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2005] [Accepted: 01/26/2006] [Indexed: 10/25/2022]
Abstract
Mononuclear molybdenum and tungsten are found in the active site of a diverse group of enzymes that, in general, catalyze oxygen atom transfer reactions. Enzymes of the xanthine oxidase family are the best-characterized mononuclear Mo-containing enzymes. Several 3D structures of diverse members of this family are known. Recently, the structures of substrate-bound and arsenite-inhibited forms of two members of this family have also been reported. In addition, spectroscopic studies have been utilized to elucidate fine details that complement the structural information. Altogether, these studies have provided an important amount of information on the characteristics of the active site and the electron transfer pathways.
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Affiliation(s)
- Carlos D Brondino
- Facultad de Bioquímica y Ciencias Biológicas, Universidad Nacional del Litoral, Campus Universitario, 3000 Santa Fe, Argentina.
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Gourlay C, Nielsen DJ, White JM, Knottenbelt SZ, Kirk ML, Young CG. Paramagnetic Active Site Models for the Molybdenum−Copper Carbon Monoxide Dehydrogenase. J Am Chem Soc 2006; 128:2164-5. [PMID: 16478141 DOI: 10.1021/ja056500f] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
New paramagnetic, heterobimetallic Mo/Cu complexes featuring the Mo(=O)(mu-S)Cu core of O. carboxidovorans carbon monoxide dehydrogenase have been synthesized and structurally and spectroscopically characterized. The complexes exhibit EPR spectra (left graphic) indicative of extensive electron delocalization across the Mo-S-Cu core, in agreement with computational studies identifying the singly-occupied molecular orbital (right graphic).
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Affiliation(s)
- Craig Gourlay
- School of Chemistry, University of Melbourne, Victoria 3010, Australia
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