1
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Park J, Heo Y, Jeon BW, Jung M, Kim YH, Lee HH, Roh SH. Structure of recombinant formate dehydrogenase from Methylobacterium extorquens (MeFDH1). Sci Rep 2024; 14:3819. [PMID: 38360844 PMCID: PMC10869683 DOI: 10.1038/s41598-024-54205-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 02/09/2024] [Indexed: 02/17/2024] Open
Abstract
Formate dehydrogenase (FDH) is critical for the conversion between formate and carbon dioxide. Despite its importance, the structural complexity of FDH and difficulties in the production of the enzyme have made elucidating its unique physicochemical properties challenging. Here, we purified recombinant Methylobacterium extorquens AM1 FDH (MeFDH1) and used cryo-electron microscopy to determine its structure. We resolved a heterodimeric MeFDH1 structure at a resolution of 2.8 Å, showing a noncanonical active site and a well-embedded Fe-S redox chain relay. In particular, the tungsten bis-molybdopterin guanine dinucleotide active site showed an open configuration with a flexible C-terminal cap domain, suggesting structural and dynamic heterogeneity in the enzyme.
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Affiliation(s)
- Junsun Park
- Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yoonyoung Heo
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Byoung Wook Jeon
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Mingyu Jung
- Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, 08826, Republic of Korea
| | - Yong Hwan Kim
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea.
| | - Hyung Ho Lee
- Department of Chemistry, College of Natural Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
| | - Soung-Hun Roh
- Department of Biological Sciences, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, 08826, Republic of Korea.
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2
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Magalon A. History of Maturation of Prokaryotic Molybdoenzymes-A Personal View. Molecules 2023; 28:7195. [PMID: 37894674 PMCID: PMC10609526 DOI: 10.3390/molecules28207195] [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: 09/25/2023] [Revised: 10/11/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
In prokaryotes, the role of Mo/W enzymes in physiology and bioenergetics is widely recognized. It is worth noting that the most diverse family of Mo/W enzymes is exclusive to prokaryotes, with the probable existence of several of them from the earliest forms of life on Earth. The structural organization of these enzymes, which often include additional redox centers, is as diverse as ever, as is their cellular localization. The most notable observation is the involvement of dedicated chaperones assisting with the assembly and acquisition of the metal centers, including Mo/W-bisPGD, one of the largest organic cofactors in nature. This review seeks to provide a new understanding and a unified model of Mo/W enzyme maturation.
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Affiliation(s)
- Axel Magalon
- Aix Marseille Université, CNRS, Laboratoire de Chimie Bactérienne (UMR7283), IMM, IM2B, 13402 Marseille, France
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3
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Leimkühler S. Metal-Containing Formate Dehydrogenases, a Personal View. Molecules 2023; 28:5338. [PMID: 37513211 PMCID: PMC10385643 DOI: 10.3390/molecules28145338] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/04/2023] [Accepted: 07/09/2023] [Indexed: 07/30/2023] Open
Abstract
Mo/W-containing formate dehydrogenases (FDH) catalyzes the reversible oxidation of formate to carbon dioxide at their molybdenum or tungsten active sites. The metal-containing FDHs are members of the dimethylsulfoxide reductase family of mononuclear molybdenum cofactor (Moco)- or tungsten cofactor (Wco)-containing enzymes. In these enzymes, the active site in the oxidized state comprises a Mo or W atom present in the bis-Moco, which is coordinated by the two dithiolene groups from the two MGD moieties, a protein-derived SeCys or Cys, and a sixth ligand that is now accepted as being a sulfido group. SeCys-containing enzymes have a generally higher turnover number than Cys-containing enzymes. The analogous chemical properties of W and Mo, the similar active sites of W- and Mo-containing enzymes, and the fact that W can replace Mo in some enzymes have led to the conclusion that Mo- and W-containing FDHs have the same reaction mechanism. Details of the catalytic mechanism of metal-containing formate dehydrogenases are still not completely understood and have been discussed here.
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Affiliation(s)
- Silke Leimkühler
- Department of Molecular Enzymology, Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
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4
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Laun K, Duffus BR, Wahlefeld S, Katz S, Belger D, Hildebrandt P, Mroginski MA, Leimkühler S, Zebger I. Infrared Spectroscopy Elucidates the Inhibitor Binding Sites in a Metal-Dependent Formate Dehydrogenase. Chemistry 2022; 28:e202201091. [PMID: 35662280 PMCID: PMC9804402 DOI: 10.1002/chem.202201091] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Indexed: 01/05/2023]
Abstract
Biological carbon dioxide (CO2 ) reduction is an important step by which organisms form valuable energy-richer molecules required for further metabolic processes. The Mo-dependent formate dehydrogenase (FDH) from Rhodobacter capsulatus catalyzes reversible formate oxidation to CO2 at a bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor. To elucidate potential substrate binding sites relevant for the mechanism, we studied herein the interaction with the inhibitory molecules azide and cyanate, which are isoelectronic to CO2 and charged as formate. We employed infrared (IR) spectroscopy in combination with density functional theory (DFT) and inhibition kinetics. One distinct inhibitory molecule was found to bind to either a non-competitive or a competitive binding site in the secondary coordination sphere of the active site. Site-directed mutagenesis of key amino acid residues in the vicinity of the bis-MGD cofactor revealed changes in both non-competitive and competitive binding, whereby the inhibitor is in case of the latter interaction presumably bound between the cofactor and the adjacent Arg587.
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Affiliation(s)
- Konstantin Laun
- Institut für ChemieMax-Volmer-Laboratorium für Biophysikalische ChemiePC14Technische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Benjamin R. Duffus
- Institut für Biochemie und BiologieMolekulare EnzymologieUniversität PotsdamKarl-Liebknecht-Strasse 24–2514476PotsdamGermany
| | - Stefan Wahlefeld
- Institut für ChemieMax-Volmer-Laboratorium für Biophysikalische ChemiePC14Technische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany,Institut für Technische BiokatalyseTechnische Universität HamburgDenickestr. 1521073HamburgGermany
| | - Sagie Katz
- Institut für ChemieMax-Volmer-Laboratorium für Biophysikalische ChemiePC14Technische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Dennis Belger
- Institut für ChemieMax-Volmer-Laboratorium für Biophysikalische ChemiePC14Technische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Peter Hildebrandt
- Institut für ChemieMax-Volmer-Laboratorium für Biophysikalische ChemiePC14Technische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Maria Andrea Mroginski
- Institut für ChemieMax-Volmer-Laboratorium für Biophysikalische ChemiePC14Technische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
| | - Silke Leimkühler
- Institut für Biochemie und BiologieMolekulare EnzymologieUniversität PotsdamKarl-Liebknecht-Strasse 24–2514476PotsdamGermany
| | - Ingo Zebger
- Institut für ChemieMax-Volmer-Laboratorium für Biophysikalische ChemiePC14Technische Universität BerlinStrasse des 17. Juni 13510623BerlinGermany
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5
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Kirk ML, Hille R. Spectroscopic Studies of Mononuclear Molybdenum Enzyme Centers. Molecules 2022; 27:molecules27154802. [PMID: 35956757 PMCID: PMC9370002 DOI: 10.3390/molecules27154802] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [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
- Correspondence: (M.L.K.); (R.H.)
| | - Russ Hille
- Department of Biochemistry, Boyce Hall 1463, University of California, Riverside, CA 82521, USA
- Correspondence: (M.L.K.); (R.H.)
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6
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Stripp ST, Duffus BR, Fourmond V, Léger C, Leimkühler S, Hirota S, Hu Y, Jasniewski A, Ogata H, Ribbe MW. Second and Outer Coordination Sphere Effects in Nitrogenase, Hydrogenase, Formate Dehydrogenase, and CO Dehydrogenase. Chem Rev 2022; 122:11900-11973. [PMID: 35849738 PMCID: PMC9549741 DOI: 10.1021/acs.chemrev.1c00914] [Citation(s) in RCA: 50] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Gases like H2, N2, CO2, and CO are increasingly recognized as critical feedstock in "green" energy conversion and as sources of nitrogen and carbon for the agricultural and chemical sectors. However, the industrial transformation of N2, CO2, and CO and the production of H2 require significant energy input, which renders processes like steam reforming and the Haber-Bosch reaction economically and environmentally unviable. Nature, on the other hand, performs similar tasks efficiently at ambient temperature and pressure, exploiting gas-processing metalloenzymes (GPMs) that bind low-valent metal cofactors based on iron, nickel, molybdenum, tungsten, and sulfur. Such systems are studied to understand the biocatalytic principles of gas conversion including N2 fixation by nitrogenase and H2 production by hydrogenase as well as CO2 and CO conversion by formate dehydrogenase, carbon monoxide dehydrogenase, and nitrogenase. In this review, we emphasize the importance of the cofactor/protein interface, discussing how second and outer coordination sphere effects determine, modulate, and optimize the catalytic activity of GPMs. These may comprise ionic interactions in the second coordination sphere that shape the electron density distribution across the cofactor, hydrogen bonding changes, and allosteric effects. In the outer coordination sphere, proton transfer and electron transfer are discussed, alongside the role of hydrophobic substrate channels and protein structural changes. Combining the information gained from structural biology, enzyme kinetics, and various spectroscopic techniques, we aim toward a comprehensive understanding of catalysis beyond the first coordination sphere.
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Affiliation(s)
- Sven T Stripp
- Freie Universität Berlin, Experimental Molecular Biophysics, Berlin 14195, Germany
| | | | - Vincent Fourmond
- Laboratoire de Bioénergétique et Ingénierie des Protéines, Institut de Microbiologie de la Méditerranée, Institut Microbiologie, Bioénergies et Biotechnologie, CNRS, Aix Marseille Université, Marseille 13402, France
| | - Christophe Léger
- Laboratoire de Bioénergétique et Ingénierie des Protéines, Institut de Microbiologie de la Méditerranée, Institut Microbiologie, Bioénergies et Biotechnologie, CNRS, Aix Marseille Université, Marseille 13402, France
| | - Silke Leimkühler
- University of Potsdam, Molecular Enzymology, Potsdam 14476, Germany
| | - Shun Hirota
- Nara Institute of Science and Technology, Division of Materials Science, Graduate School of Science and Technology, Nara 630-0192, Japan
| | - Yilin Hu
- Department of Molecular Biology & Biochemistry, University of California, Irvine, California 92697-3900, United States
| | - Andrew Jasniewski
- Department of Molecular Biology & Biochemistry, University of California, Irvine, California 92697-3900, United States
| | - Hideaki Ogata
- Nara Institute of Science and Technology, Division of Materials Science, Graduate School of Science and Technology, Nara 630-0192, Japan.,Hokkaido University, Institute of Low Temperature Science, Sapporo 060-0819, Japan.,Graduate School of Science, University of Hyogo, Hyogo 678-1297, Japan
| | - Markus W Ribbe
- Department of Molecular Biology & Biochemistry, University of California, Irvine, California 92697-3900, United States.,Department of Chemistry, University of California, Irvine, California 92697-2025, United States
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7
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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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8
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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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9
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Arias-Cartin R, Uzel A, Seduk F, Gerbaud G, Pierrel F, Broc M, Lebrun R, Guigliarelli B, Magalon A, Grimaldi S, Walburger A. Identification and characterization of a non-canonical menaquinone-linked formate dehydrogenase. J Biol Chem 2021; 298:101384. [PMID: 34748728 PMCID: PMC8808070 DOI: 10.1016/j.jbc.2021.101384] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 10/18/2021] [Accepted: 10/20/2021] [Indexed: 10/25/2022] Open
Abstract
The Molybdenum/Tungsten-bispyranopterin guanine dinucleotides (Mo/W-bisPGD) family of Formate Dehydrogenases (FDHs) plays roles in several metabolic pathways ranging from carbon fixation to energy harvesting owing to their reaction with a wide variety of redox partners. Indeed, this metabolic plasticity results from the diverse structures, cofactor content, and substrates employed by partner subunits interacting with the catalytic hub. Here, we unveiled two non-canonical FDHs in Bacillus subtilis which are organized into two-subunit complexes with unique features, ForCE1 and ForCE2. We show that the ForC catalytic subunit interacts with an unprecedented partner subunit, ForE, and that its amino acid sequence within the active site deviates from the consensus residues typically associated with FDH activity, as a histidine residue is naturally substituted with a glutamine. The ForE essential subunit mediates the utilization of menaquinone as an electron acceptor as shown by the formate:menadione oxidoreductase activity of both enzymes, their copurification with menaquinone, and the distinctive detection of a protein-bound neutral menasemiquinone radical by multifrequency electron paramagnetic resonance (EPR) experiments on the purified enzymes. Moreover, EPR characterization of both FDHs reveals the presence of several [Fe-S] clusters with distinct relaxation properties and a weakly anisotropic Mo(V) EPR signature, consistent with the characteristic Mo/bisPGD cofactor of this enzyme family. Altogether, this work enlarges our knowledge of the FDH family by identifying a non-canonical FDH, which differs in terms of architecture, amino acid conservation around the Mo cofactor, and reactivity.
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Affiliation(s)
- Rodrigo Arias-Cartin
- Aix Marseille Université, CNRS, Laboratoire de Chimie Bactérienne (UMR7283), IMM, IM2B, 13009 Marseille, France; Aix Marseille Université, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (UMR7281), IMM, IM2B, 13009 Marseille, France.
| | - Alexandre Uzel
- Aix Marseille Université, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (UMR7281), IMM, IM2B, 13009 Marseille, France
| | - Farida Seduk
- Aix Marseille Université, CNRS, Laboratoire de Chimie Bactérienne (UMR7283), IMM, IM2B, 13009 Marseille, France
| | - Guillaume Gerbaud
- Aix Marseille Université, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (UMR7281), IMM, IM2B, 13009 Marseille, France
| | - Fabien Pierrel
- Grenoble Alpes Université, CNRS, Grenoble INP, TIMC, 38000 Grenoble, France
| | - Marianne Broc
- Aix Marseille Université, CNRS, Laboratoire de Chimie Bactérienne (UMR7283), IMM, IM2B, 13009 Marseille, France
| | - Régine Lebrun
- Aix Marseille Université, CNRS, Plateforme Protéomique de l'IMM, IM2B Marseille Protéomique (MaP), 13009 Marseille, France
| | - Bruno Guigliarelli
- Aix Marseille Université, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (UMR7281), IMM, IM2B, 13009 Marseille, France
| | - Axel Magalon
- Aix Marseille Université, CNRS, Laboratoire de Chimie Bactérienne (UMR7283), IMM, IM2B, 13009 Marseille, France
| | - Stéphane Grimaldi
- Aix Marseille Université, CNRS, Laboratoire de Bioénergétique et Ingénierie des Protéines (UMR7281), IMM, IM2B, 13009 Marseille, France.
| | - Anne Walburger
- Aix Marseille Université, CNRS, Laboratoire de Chimie Bactérienne (UMR7283), IMM, IM2B, 13009 Marseille, France.
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10
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The Requirement of Inorganic Fe-S Clusters for the Biosynthesis of the Organometallic Molybdenum Cofactor. INORGANICS 2020. [DOI: 10.3390/inorganics8070043] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Iron-sulfur (Fe-S) clusters are essential protein cofactors. In enzymes, they are present either in the rhombic [2Fe-2S] or the cubic [4Fe-4S] form, where they are involved in catalysis and electron transfer and in the biosynthesis of metal-containing prosthetic groups like the molybdenum cofactor (Moco). Here, we give an overview of the assembly of Fe-S clusters in bacteria and humans and present their connection to the Moco biosynthesis pathway. In all organisms, Fe-S cluster assembly starts with the abstraction of sulfur from l-cysteine and its transfer to a scaffold protein. After formation, Fe-S clusters are transferred to carrier proteins that insert them into recipient apo-proteins. In eukaryotes like humans and plants, Fe-S cluster assembly takes place both in mitochondria and in the cytosol. Both Moco biosynthesis and Fe-S cluster assembly are highly conserved among all kingdoms of life. Moco is a tricyclic pterin compound with molybdenum coordinated through its unique dithiolene group. Moco biosynthesis begins in the mitochondria in a Fe-S cluster dependent step involving radical/S-adenosylmethionine (SAM) chemistry. An intermediate is transferred to the cytosol where the dithiolene group is formed, to which molybdenum is finally added. Further connections between Fe-S cluster assembly and Moco biosynthesis are discussed in detail.
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11
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Functional mononuclear molybdenum enzymes: challenges and triumphs in molecular cloning, expression, and isolation. J Biol Inorg Chem 2020; 25:547-569. [PMID: 32279136 DOI: 10.1007/s00775-020-01787-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 03/30/2020] [Indexed: 10/24/2022]
Abstract
Mononuclear molybdenum enzymes catalyze a variety of reactions that are essential in the cycling of nitrogen, carbon, arsenic, and sulfur. For decades, the structure and function of these crucial enzymes have been investigated to develop a fundamental knowledge for this vast family of enzymes and the chemistries they carry out. Therefore, obtaining abundant quantities of active enzyme is necessary for exploring this family's biochemical capability. This mini-review summarizes the methods for overexpressing mononuclear molybdenum enzymes in the context of the challenges encountered in the process. Effective methods for molybdenum cofactor synthesis and incorporation, optimization of expression conditions, improving isolation of active vs. inactive enzyme, incorporation of additional prosthetic groups, and inclusion of redox enzyme maturation protein chaperones are discussed in relation to the current molybdenum enzyme literature. This article summarizes the heterologous and homologous expression studies providing underlying patterns and potential future directions.
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12
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Leimkühler S. The biosynthesis of the molybdenum cofactors in Escherichia coli. Environ Microbiol 2020; 22:2007-2026. [PMID: 32239579 DOI: 10.1111/1462-2920.15003] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 03/10/2020] [Accepted: 03/11/2020] [Indexed: 12/29/2022]
Abstract
The biosynthesis of the molybdenum cofactor (Moco) is highly conserved among all kingdoms of life. In all molybdoenzymes containing Moco, the molybdenum atom is coordinated to a dithiolene group present in the pterin-based 6-alkyl side chain of molybdopterin (MPT). In general, the biosynthesis of Moco can be divided into four steps in in bacteria: (i) the starting point is the formation of the cyclic pyranopterin monophosphate (cPMP) from 5'-GTP, (ii) in the second step the two sulfur atoms are inserted into cPMP leading to the formation of MPT, (iii) in the third step the molybdenum atom is inserted into MPT to form Moco and (iv) in the fourth step bis-Mo-MPT is formed and an additional modification of Moco is possible with the attachment of a nucleotide (CMP or GMP) to the phosphate group of MPT, forming the dinucleotide variants of Moco. This review presents an update on the well-characterized Moco biosynthesis in the model organism Escherichia coli including novel discoveries from the recent years.
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Affiliation(s)
- Silke Leimkühler
- Department of Molecular Enzymology, Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
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13
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Classification and enzyme kinetics of formate dehydrogenases for biomanufacturing via CO2 utilization. Biotechnol Adv 2019; 37:107408. [DOI: 10.1016/j.biotechadv.2019.06.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/26/2019] [Accepted: 06/10/2019] [Indexed: 12/14/2022]
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14
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Niks D, Hille R. Molybdenum- and tungsten-containing formate dehydrogenases and formylmethanofuran dehydrogenases: Structure, mechanism, and cofactor insertion. Protein Sci 2019; 28:111-122. [PMID: 30120799 PMCID: PMC6295890 DOI: 10.1002/pro.3498] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/10/2018] [Accepted: 08/13/2018] [Indexed: 12/20/2022]
Abstract
An overview is provided of the molybdenum- and tungsten-containing enzymes that catalyze the interconversion of formate and CO2 , focusing on common structural and mechanistic themes, as well as a consideration of the manner in which the mature Mo- or W-containing cofactor is inserted into apoprotein.
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Affiliation(s)
- Dimitri Niks
- Department of BiochemistryUniversity of CaliforniaRiverside
| | - Russ Hille
- Department of BiochemistryUniversity of CaliforniaRiverside
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15
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Schwanhold N, Iobbi-Nivol C, Lehmann A, Leimkühler S. Same but different: Comparison of two system-specific molecular chaperones for the maturation of formate dehydrogenases. PLoS One 2018; 13:e0201935. [PMID: 30444874 PMCID: PMC6239281 DOI: 10.1371/journal.pone.0201935] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 08/21/2018] [Indexed: 11/19/2022] Open
Abstract
The maturation of bacterial molybdoenzymes is a complex process leading to the insertion of the bulky bis-molybdopterin guanine dinucleotide (bis-MGD) cofactor into the apo-enzyme. Most molybdoenzymes were shown to contain a specific chaperone for the insertion of the bis-MGD cofactor. Formate dehydrogenases (FDH) together with their molecular chaperone partner seem to display an exception to this specificity rule, since the chaperone FdhD has been proven to be involved in the maturation of all three FDH enzymes present in Escherichia coli. Multiple roles have been suggested for FdhD-like chaperones in the past, including the involvement in a sulfur transfer reaction from the l-cysteine desulfurase IscS to bis-MGD by the action of two cysteine residues present in a conserved CXXC motif of the chaperones. However, in this study we show by phylogenetic analyses that the CXXC motif is not conserved among FdhD-like chaperones. We compared in detail the FdhD-like homologues from Rhodobacter capsulatus and E. coli and show that their roles in the maturation of FDH enzymes from different subgroups can be exchanged. We reveal that bis-MGD-binding is a common characteristic of FdhD-like proteins and that the cofactor is bound with a sulfido-ligand at the molybdenum atom to the chaperone. Generally, we reveal that the cysteine residues in the motif CXXC of the chaperone are not essential for the production of active FDH enzymes.
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Affiliation(s)
- Nadine Schwanhold
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, Potsdam, Germany
| | | | - Angelika Lehmann
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, Potsdam, Germany
| | - Silke Leimkühler
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, Potsdam, Germany
- * E-mail:
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16
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Cazelles R, Lalaoui N, Hartmann T, Leimkühler S, Wollenberger U, Antonietti M, Cosnier S. Ready to use bioinformatics analysis as a tool to predict immobilisation strategies for protein direct electron transfer (DET). Biosens Bioelectron 2016; 85:90-95. [PMID: 27156017 DOI: 10.1016/j.bios.2016.04.078] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 04/20/2016] [Accepted: 04/22/2016] [Indexed: 12/19/2022]
Abstract
Direct electron transfer (DET) to proteins is of considerable interest for the development of biosensors and bioelectrocatalysts. While protein structure is mainly used as a method of attaching the protein to the electrode surface, we employed bioinformatics analysis to predict the suitable orientation of the enzymes to promote DET. Structure similarity and secondary structure prediction were combined underlying localized amino-acids able to direct one of the enzyme's electron relays toward the electrode surface by creating a suitable bioelectrocatalytic nanostructure. The electro-polymerization of pyrene pyrrole onto a fluorine-doped tin oxide (FTO) electrode allowed the targeted orientation of the formate dehydrogenase enzyme from Rhodobacter capsulatus (RcFDH) by means of hydrophobic interactions. Its electron relays were directed to the FTO surface, thus promoting DET. The reduction of nicotinamide adenine dinucleotide (NAD(+)) generating a maximum current density of 1μAcm(-2) with 10mM NAD(+) leads to a turnover number of 0.09electron/s/molRcFDH. This work represents a practical approach to evaluate electrode surface modification strategies in order to create valuable bioelectrocatalysts.
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Affiliation(s)
- R Cazelles
- Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476 Potsdam (Golm), Germany.
| | - N Lalaoui
- Univ. Grenoble Alpes, CNRS, DCM UMR 5250, F-38000 Grenoble, France
| | - T Hartmann
- Department of Molecular Enzymology, Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam (Golm), Germany
| | - S Leimkühler
- Department of Molecular Enzymology, Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam (Golm), Germany
| | - U Wollenberger
- Department of Molecular Enzymology, Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam (Golm), Germany
| | - M Antonietti
- Max Planck Institute of Colloids and Interfaces, Am Mühlenberg 1, 14476 Potsdam (Golm), Germany
| | - S Cosnier
- Univ. Grenoble Alpes, CNRS, DCM UMR 5250, F-38000 Grenoble, France
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Hartmann T, Schrapers P, Utesch T, Nimtz M, Rippers Y, Dau H, Mroginski MA, Haumann M, Leimkühler S. The Molybdenum Active Site of Formate Dehydrogenase Is Capable of Catalyzing C–H Bond Cleavage and Oxygen Atom Transfer Reactions. Biochemistry 2016; 55:2381-9. [DOI: 10.1021/acs.biochem.6b00002] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Tobias Hartmann
- Department
of Molecular Enzymology, Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht Strasse 24-25, 14476 Potsdam, Germany
| | - Peer Schrapers
- Institute
of Experimental Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Tillmann Utesch
- Institute
of Chemistry, Technical University of Berlin, Straße des 17. Juni135, 10623 Berlin, Germany
| | - Manfred Nimtz
- Helmholtz Center for Infection Research, Inhoffenstraße 7, 38124 Braunschweig, Germany
| | - Yvonne Rippers
- Institute
of Chemistry, Technical University of Berlin, Straße des 17. Juni135, 10623 Berlin, Germany
| | - Holger Dau
- Institute
of Experimental Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Maria Andrea Mroginski
- Institute
of Chemistry, Technical University of Berlin, Straße des 17. Juni135, 10623 Berlin, Germany
| | - Michael Haumann
- Institute
of Experimental Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Silke Leimkühler
- Department
of Molecular Enzymology, Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht Strasse 24-25, 14476 Potsdam, Germany
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18
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Leimkühler S, Iobbi-Nivol C. Bacterial molybdoenzymes: old enzymes for new purposes. FEMS Microbiol Rev 2015; 40:1-18. [PMID: 26468212 DOI: 10.1093/femsre/fuv043] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/05/2015] [Indexed: 02/06/2023] Open
Abstract
Molybdoenzymes are widespread in eukaryotic and prokaryotic organisms where they play crucial functions in detoxification reactions in the metabolism of humans and bacteria, in nitrate assimilation in plants and in anaerobic respiration in bacteria. To be fully active, these enzymes require complex molybdenum-containing cofactors, which are inserted into the apoenzymes after folding. For almost all the bacterial molybdoenzymes, molybdenum cofactor insertion requires the involvement of specific chaperones. In this review, an overview on the molybdenum cofactor biosynthetic pathway is given together with the role of specific chaperones dedicated for molybdenum cofactor insertion and maturation. Many bacteria are involved in geochemical cycles on earth and therefore have an environmental impact. The roles of molybdoenzymes in bioremediation and for environmental applications are presented.
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Affiliation(s)
- Silke Leimkühler
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, 14476 Potsdam, Germany
| | - Chantal Iobbi-Nivol
- The Laboratoire de Bioénergétique et Ingénierie des Protéines, Institut de Microbiologie de la Méditerranée, CNRS, Aix Marseille Université, 13402 Marseille cedex 20, France
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19
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Schrapers P, Hartmann T, Kositzki R, Dau H, Reschke S, Schulzke C, Leimkühler S, Haumann M. Sulfido and cysteine ligation changes at the molybdenum cofactor during substrate conversion by formate dehydrogenase (FDH) from Rhodobacter capsulatus. Inorg Chem 2015; 54:3260-71. [PMID: 25803130 DOI: 10.1021/ic502880y] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Formate dehydrogenase (FDH) enzymes are attractive catalysts for potential carbon dioxide conversion applications. The FDH from Rhodobacter capsulatus (RcFDH) binds a bis-molybdopterin-guanine-dinucleotide (bis-MGD) cofactor, facilitating reversible formate (HCOO(-)) to CO2 oxidation. We characterized the molecular structure of the active site of wildtype RcFDH and protein variants using X-ray absorption spectroscopy (XAS) at the Mo K-edge. This approach has revealed concomitant binding of a sulfido ligand (Mo=S) and a conserved cysteine residue (S(Cys386)) to Mo(VI) in the active oxidized molybdenum cofactor (Moco), retention of such a coordination motif at Mo(V) in a chemically reduced enzyme, and replacement of only the S(Cys386) ligand by an oxygen of formate upon Mo(IV) formation. The lack of a Mo=S bond in RcFDH expressed in the absence of FdsC implies specific metal sulfuration by this bis-MGD binding chaperone. This process still functioned in the Cys386Ser variant, showing no Mo-S(Cys386) ligand, but retaining a Mo=S bond. The C386S variant and the protein expressed without FdsC were inactive in formate oxidation, supporting that both Mo-ligands are essential for catalysis. Low-pH inhibition of RcFDH was attributed to protonation at the conserved His387, supported by the enhanced activity of the His387Met variant at low pH, whereas inactive cofactor species showed sulfido-to-oxo group exchange at the Mo ion. Our results support that the sulfido and S(Cys386) ligands at Mo and a hydrogen-bonded network including His387 are crucial for positioning, deprotonation, and oxidation of formate during the reaction cycle of RcFDH.
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Affiliation(s)
- Peer Schrapers
- †Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany
| | - Tobias Hartmann
- ‡Institut für Biochemie und Biologie, Molekulare Enzymologie, Universität Potsdam, 14476 Potsdam, Germany
| | - Ramona Kositzki
- †Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany
| | - Holger Dau
- †Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany
| | - Stefan Reschke
- ‡Institut für Biochemie und Biologie, Molekulare Enzymologie, Universität Potsdam, 14476 Potsdam, Germany
| | - Carola Schulzke
- §Institut für Biochemie, Bioanorganische Chemie, Ernst-Moritz-Arndt-Universität Greifswald, 17487 Greifswald, Germany
| | - Silke Leimkühler
- ‡Institut für Biochemie und Biologie, Molekulare Enzymologie, Universität Potsdam, 14476 Potsdam, Germany
| | - Michael Haumann
- †Institut für Experimentalphysik, Freie Universität Berlin, 14195 Berlin, Germany
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20
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Sulphur shuttling across a chaperone during molybdenum cofactor maturation. Nat Commun 2015; 6:6148. [PMID: 25649206 DOI: 10.1038/ncomms7148] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 12/15/2014] [Indexed: 11/09/2022] Open
Abstract
Formate dehydrogenases (FDHs) are of interest as they are natural catalysts that sequester atmospheric CO2, generating reduced carbon compounds with possible uses as fuel. FDHs activity in Escherichia coli strictly requires the sulphurtransferase EcFdhD, which likely transfers sulphur from IscS to the molybdenum cofactor (Mo-bisPGD) of FDHs. Here we show that EcFdhD binds Mo-bisPGD in vivo and has submicromolar affinity for GDP-used as a surrogate of the molybdenum cofactor's nucleotide moieties. The crystal structure of EcFdhD in complex with GDP shows two symmetrical binding sites located on the same face of the dimer. These binding sites are connected via a tunnel-like cavity to the opposite face of the dimer where two dynamic loops, each harbouring two functionally important cysteine residues, are present. On the basis of structure-guided mutagenesis, we propose a model for the sulphuration mechanism of Mo-bisPGD where the sulphur atom shuttles across the chaperone dimer.
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Hartmann T, Schwanhold N, Leimkühler S. Assembly and catalysis of molybdenum or tungsten-containing formate dehydrogenases from bacteria. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1854:1090-100. [PMID: 25514355 DOI: 10.1016/j.bbapap.2014.12.006] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 12/04/2014] [Accepted: 12/06/2014] [Indexed: 11/28/2022]
Abstract
The global carbon cycle depends on the biological transformations of C1 compounds, which include the reductive incorporation of CO₂into organic molecules (e.g. in photosynthesis and other autotrophic pathways), in addition to the production of CO₂from formate, a reaction that is catalyzed by formate dehydrogenases (FDHs). FDHs catalyze, in general, the oxidation of formate to CO₂and H⁺. However, selected enzymes were identified to act as CO₂reductases, which are able to reduce CO₂to formate under physiological conditions. This reaction is of interest for the generation of formate as a convenient storage form of H₂for future applications. Cofactor-containing FDHs are found in anaerobic bacteria and archaea, in addition to facultative anaerobic or aerobic bacteria. These enzymes are highly diverse and employ different cofactors such as the molybdenum cofactor (Moco), FeS clusters and flavins, or cytochromes. Some enzymes include tungsten (W) in place of molybdenum (Mo) at the active site. For catalytic activity, a selenocysteine (SeCys) or cysteine (Cys) ligand at the Mo atom in the active site is essential for the reaction. This review will focus on the characterization of Mo- and W-containing FDHs from bacteria, their active site structure, subunit compositions and its proposed catalytic mechanism. We will give an overview on the different mechanisms of substrate conversion available so far, in addition to providing an outlook on bio-applications of FDHs. This article is part of a Special Issue entitled: Cofactor-dependent proteins: evolution, chemical diversity and bio-applications.
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Affiliation(s)
- Tobias Hartmann
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, D-14476 Potsdam, Germany
| | - Nadine Schwanhold
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, D-14476 Potsdam, Germany
| | - Silke Leimkühler
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, D-14476 Potsdam, Germany.
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22
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Yokoyama K, Leimkühler S. The role of FeS clusters for molybdenum cofactor biosynthesis and molybdoenzymes in bacteria. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:1335-49. [PMID: 25268953 DOI: 10.1016/j.bbamcr.2014.09.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 09/19/2014] [Accepted: 09/22/2014] [Indexed: 11/29/2022]
Abstract
The biosynthesis of the molybdenum cofactor (Moco) has been intensively studied, in addition to its insertion into molybdoenzymes. In particular, a link between the assembly of molybdoenzymes and the biosynthesis of FeS clusters has been identified in the recent years: 1) the synthesis of the first intermediate in Moco biosynthesis requires an FeS-cluster containing protein, 2) the sulfurtransferase for the dithiolene group in Moco is also involved in the synthesis of FeS clusters, thiamin and thiolated tRNAs, 3) the addition of a sulfido-ligand to the molybdenum atom in the active site additionally involves a sulfurtransferase, and 4) most molybdoenzymes in bacteria require FeS clusters as redox active cofactors. In this review we will focus on the biosynthesis of the molybdenum cofactor in bacteria, its modification and insertion into molybdoenzymes, with an emphasis to its link to FeS cluster biosynthesis and sulfur transfer.
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Affiliation(s)
- Kenichi Yokoyama
- Department of Biochemistry, Duke University Medical Center, Durham, NC, USA
| | - Silke Leimkühler
- Department of Molecular Enzymology, Institute of Biochemistry and Biology, University of Potsdam, 14476 Potsdam, Germany.
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23
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Mendel RR, Leimkühler S. The biosynthesis of the molybdenum cofactors. J Biol Inorg Chem 2014; 20:337-47. [PMID: 24980677 DOI: 10.1007/s00775-014-1173-y] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 06/09/2014] [Indexed: 12/11/2022]
Abstract
The biosynthesis of the molybdenum cofactors (Moco) is an ancient, ubiquitous, and highly conserved pathway leading to the biochemical activation of molybdenum. Moco is the essential component of a group of redox enzymes, which are diverse in terms of their phylogenetic distribution and their architectures, both at the overall level and in their catalytic geometry. A wide variety of transformations are catalyzed by these enzymes at carbon, sulfur and nitrogen atoms, which include the transfer of an oxo group or two electrons to or from the substrate. More than 50 molybdoenzymes were identified to date. In all molybdoenzymes except nitrogenase, molybdenum is coordinated to a dithiolene group on the 6-alkyl side chain of a pterin called molybdopterin (MPT). The biosynthesis of Moco can be divided into three general steps, with a fourth one present only in bacteria and archaea: (1) formation of the cyclic pyranopterin monophosphate, (2) formation of MPT, (3) insertion of molybdenum into molybdopterin to form Moco, and (4) additional modification of Moco in bacteria with the attachment of a nucleotide to the phosphate group of MPT, forming the dinucleotide variant of Moco. This review will focus on the biosynthesis of Moco in bacteria, humans and plants.
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Affiliation(s)
- Ralf R Mendel
- Institute of Plant Biology, Braunschweig University of Technology, Humboldtstr. 1, 38106, Braunschweig, Germany,
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24
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The Biosynthesis of the Molybdenum Cofactor in Escherichia coli and Its Connection to FeS Cluster Assembly and the Thiolation of tRNA. ACTA ACUST UNITED AC 2014. [DOI: 10.1155/2014/808569] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The thiolation of biomolecules is a complex process that involves the activation of sulfur. The L-cysteine desulfurase IscS is the main sulfur mobilizing protein in Escherichia coli that provides the sulfur from L-cysteine to several important biomolecules in the cell such as iron sulfur (FeS) clusters, molybdopterin (MPT), thiamine, and thionucleosides of tRNA. Various proteins mediate the transfer of sulfur from IscS to various biomolecules using different interaction partners. A direct connection between the sulfur-containing molecules FeS clusters, thiolated tRNA, and the molybdenum cofactor (Moco) has been identified. The first step of Moco biosynthesis involves the conversion of 5′GTP to cyclic pyranopterin monophosphate (cPMP), a reaction catalyzed by a FeS cluster containing protein. Formed cPMP is further converted to MPT by insertion of two sulfur atoms. The sulfur for this reaction is provided by the L-cysteine desulfurase IscS in addition to the involvement of the TusA protein. TusA is also involved in the sulfur transfer for the thiolation of tRNA. This review will describe the biosynthesis of Moco in E. coli in detail and dissects the sulfur transfer pathways for Moco and tRNA and their connection to FeS cluster biosynthesis.
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