1
|
Duffus BR, Gauglitz M, Teutloff C, Leimkühler S. Redox potentials elucidate the electron transfer pathway of NAD +-dependent formate dehydrogenases. J Inorg Biochem 2024; 253:112487. [PMID: 38306887 DOI: 10.1016/j.jinorgbio.2024.112487] [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: 10/24/2023] [Revised: 01/16/2024] [Accepted: 01/16/2024] [Indexed: 02/04/2024]
Abstract
Metal-dependent, nicotine adenine dinucleotide (NAD+)-dependent formate dehydrogenases (FDHs) are complex metalloenzymes coupling biochemical transformations through intricate electron transfer pathways. Rhodobacter capsulatus FDH is a model enzyme for understanding coupled catalysis, in that reversible CO2 reduction and formate oxidation are linked to a flavin mononuclotide (FMN)-bound diaphorase module via seven iron-sulfur (FeS) clusters as a dimer of heterotetramers. Catalysis occurs at a bis-metal-binding pterin (Mo) binding two molybdopterin guanine dinucleotides (bis-MGD), a protein-based Cys residue and a participatory sulfido ligand. Insights regarding the proposed electron transfer mechanism between the bis-MGD and the FMN have been complicated by the discovery that an alternative pathway might occur via intersubunit electron transfer between two [4Fe4S] clusters within electron transfer distance. To clarify this difference, the redox potentials of the bis-MGD and the FeS clusters were determined via redox titration by EPR spectroscopy. Redox potentials for the bis-MGD cofactor and five of the seven FeS clusters could be assigned. Furthermore, substitution of the active site residue Lys295 with Ala resulted in altered enzyme kinetics, primarily due to a more negative redox potential of the A1 [4Fe4S] cluster. Finally, characterization of the monomeric FdsGBAD heterotetramer exhibited slightly decreased formate oxidation activity and similar iron-sulfur clusters reduced relative to the dimeric heterotetramer. Comparison of the measured redox potentials relative to structurally defined FeS clusters support a mechanism by which electron transfer occurs within a heterotetrameric unit, with the interfacial [4Fe4S] cluster serving as a structural component toward the integrity of the heterodimeric structure to drive efficient catalysis.
Collapse
Affiliation(s)
- Benjamin R Duffus
- Institute for Biochemistry and Biology, Molecular Enzymology, University of Potsdam, Karl-Liebknecht-Strasse 24-25, 14476 Potsdam, Germany
| | - Marcel Gauglitz
- Institute for Experimental Physics, Free University of Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Christian Teutloff
- Institute for Experimental Physics, Free University of Berlin, Arnimallee 14, 14195 Berlin, Germany.
| | - Silke Leimkühler
- Institute for Biochemistry and Biology, Molecular Enzymology, University of Potsdam, Karl-Liebknecht-Strasse 24-25, 14476 Potsdam, Germany.
| |
Collapse
|
2
|
Maia LB, Maiti BK, Moura I, Moura JJG. Selenium-More than Just a Fortuitous Sulfur Substitute in Redox Biology. Molecules 2023; 29:120. [PMID: 38202704 PMCID: PMC10779653 DOI: 10.3390/molecules29010120] [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: 11/30/2023] [Revised: 12/19/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024] Open
Abstract
Living organisms use selenium mainly in the form of selenocysteine in the active site of oxidoreductases. Here, selenium's unique chemistry is believed to modulate the reaction mechanism and enhance the catalytic efficiency of specific enzymes in ways not achievable with a sulfur-containing cysteine. However, despite the fact that selenium/sulfur have different physicochemical properties, several selenoproteins have fully functional cysteine-containing homologues and some organisms do not use selenocysteine at all. In this review, selected selenocysteine-containing proteins will be discussed to showcase both situations: (i) selenium as an obligatory element for the protein's physiological function, and (ii) selenium presenting no clear advantage over sulfur (functional proteins with either selenium or sulfur). Selenium's physiological roles in antioxidant defence (to maintain cellular redox status/hinder oxidative stress), hormone metabolism, DNA synthesis, and repair (maintain genetic stability) will be also highlighted, as well as selenium's role in human health. Formate dehydrogenases, hydrogenases, glutathione peroxidases, thioredoxin reductases, and iodothyronine deiodinases will be herein featured.
Collapse
Affiliation(s)
- Luisa B. Maia
- LAQV, REQUIMTE, Department of Chemistry, NOVA School of Science and Technology | NOVA FCT, 2829-516 Caparica, Portugal; (I.M.); (J.J.G.M.)
| | - Biplab K. Maiti
- Department of Chemistry, School of Sciences, Cluster University of Jammu, Canal Road, Jammu 180001, India
| | - Isabel Moura
- LAQV, REQUIMTE, Department of Chemistry, NOVA School of Science and Technology | NOVA FCT, 2829-516 Caparica, Portugal; (I.M.); (J.J.G.M.)
| | - José J. G. Moura
- LAQV, REQUIMTE, Department of Chemistry, NOVA School of Science and Technology | NOVA FCT, 2829-516 Caparica, Portugal; (I.M.); (J.J.G.M.)
| |
Collapse
|
3
|
Kumar H, Leimkühler S. Changing the Electron Acceptor Specificity of Rhodobacter capsulatus Formate Dehydrogenase from NAD + to NADP . Int J Mol Sci 2023; 24:16067. [PMID: 38003259 PMCID: PMC10671435 DOI: 10.3390/ijms242216067] [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: 10/21/2023] [Revised: 11/03/2023] [Accepted: 11/06/2023] [Indexed: 11/26/2023] Open
Abstract
Formate dehydrogenases catalyze the reversible oxidation of formate to carbon dioxide. These enzymes play an important role in CO2 reduction and serve as nicotinamide cofactor recycling enzymes. More recently, the CO2-reducing activity of formate dehydrogenases, especially metal-containing formate dehydrogenases, has been further explored for efficient atmospheric CO2 capture. Here, we investigate the nicotinamide binding site of formate dehydrogenase from Rhodobacter capsulatus for its specificity toward NAD+ vs. NADP+ reduction. Starting from the NAD+-specific wild-type RcFDH, key residues were exchanged to enable NADP+ binding on the basis of the NAD+-bound cryo-EM structure (PDB-ID: 6TG9). It has been observed that the lysine at position 157 (Lys157) in the β-subunit of the enzyme is essential for the binding of NAD+. RcFDH variants that had Glu259 exchanged for either a positively charged or uncharged amino acid had additional activity with NADP+. The FdsBL279R and FdsBK276A variants also showed activity with NADP+. Kinetic parameters for all the variants were determined and tested for activity in CO2 reduction. The variants were able to reduce CO2 using NADPH as an electron donor in a coupled assay with phosphite dehydrogenase (PTDH), which regenerates NADPH. This makes the enzyme suitable for applications where it can be coupled with other enzymes that use NADPH.
Collapse
Affiliation(s)
| | - Silke Leimkühler
- Department of Molecular Enzymology, Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany;
| |
Collapse
|
4
|
Kobayashi A, Taketa M, Sowa K, Kano K, Higuchi Y, Ogata H. Structure and function relationship of formate dehydrogenases: an overview of recent progress. IUCRJ 2023; 10:544-554. [PMID: 37668215 PMCID: PMC10478512 DOI: 10.1107/s2052252523006437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 07/24/2023] [Indexed: 09/06/2023]
Abstract
Formate dehydrogenases (FDHs) catalyze the two-electron oxidation of formate to carbon dioxide. FDHs can be divided into several groups depending on their subunit composition and active-site metal ions. Metal-dependent (Mo- or W-containing) FDHs from prokaryotic organisms belong to the superfamily of molybdenum enzymes and are members of the dimethylsulfoxide reductase family. In this short review, recent progress in the structural analysis of FDHs together with their potential biotechnological applications are summarized.
Collapse
Affiliation(s)
- Ami Kobayashi
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Midori Taketa
- Graduate School of Science, University of Hyogo, Koto 3-2-1 Kamigori, Ako, Hyogo 678-1297, Japan
| | - Keisei Sowa
- Division of Applied Life Sciences, Graduate School of Agriculture, Kyoto University, Sakyo, Kyoto 606-8502, Japan
| | - Kenji Kano
- Office of Society Academia Collaboration for Innovation, Kyoto University, Gokasho, Uji 611-0011, Japan
| | - Yoshiki Higuchi
- Graduate School of Science, University of Hyogo, Koto 3-2-1 Kamigori, Ako, Hyogo 678-1297, Japan
| | - Hideaki Ogata
- Graduate School of Science, University of Hyogo, Koto 3-2-1 Kamigori, Ako, Hyogo 678-1297, Japan
| |
Collapse
|
5
|
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.
Collapse
Affiliation(s)
- Silke Leimkühler
- Department of Molecular Enzymology, Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
| |
Collapse
|
6
|
The Mechanism of Metal-Containing Formate Dehydrogenases Revisited: The Formation of Bicarbonate as Product Intermediate Provides Evidence for an Oxygen Atom Transfer Mechanism. Molecules 2023; 28:molecules28041537. [PMID: 36838526 PMCID: PMC9962302 DOI: 10.3390/molecules28041537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 01/31/2023] [Accepted: 02/02/2023] [Indexed: 02/09/2023] Open
Abstract
Mo/W-containing formate dehydrogenases (FDH) catalyzed the reversible oxidation of formate to carbon dioxide at their molybdenum or tungsten active sites. While in the reaction of formate oxidation, the product is CO2, which exits the active site via a hydrophobic channel; bicarbonate is formed as the first intermediate during the reaction at the active site. Other than what has been previously reported, bicarbonate is formed after an oxygen atom transfer reaction, transferring the oxygen from water to formate and a subsequent proton-coupled electron transfer or hydride transfer reaction involving the sulfido ligand as acceptor.
Collapse
|
7
|
Meneghello M, Uzel A, Broc M, Manuel RR, Magalon A, Léger C, Pereira IAC, Walburger A, Fourmond V. Electrochemical Kinetics Support a Second Coordination Sphere Mechanism in Metal-Based Formate Dehydrogenase. Angew Chem Int Ed Engl 2023; 62:e202212224. [PMID: 36465058 PMCID: PMC10107981 DOI: 10.1002/anie.202212224] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/28/2022] [Accepted: 12/02/2022] [Indexed: 12/07/2022]
Abstract
Metal-based formate dehydrogenases are molybdenum or tungsten-dependent enzymes that catalyze the interconversion between formate and CO2 . According to the current consensus, the metal ion of the catalytic center in its active form is coordinated by 6 S (or 5 S and 1 Se) atoms, leaving no free coordination sites to which formate could bind to the metal. Some authors have proposed that one of the active site ligands decoordinates during turnover to allow formate binding. Another proposal is that the oxidation of formate takes place in the second coordination sphere of the metal. Here, we have used electrochemical steady-state kinetics to elucidate the order of the steps in the catalytic cycle of two formate dehydrogenases. Our results strongly support the "second coordination sphere" hypothesis.
Collapse
Affiliation(s)
- Marta Meneghello
- CNRS, Aix Marseille Université, BIP, IMM, IM2B, 31 Chemin J. Aiguier, 13009, Marseille, France
| | - Alexandre Uzel
- CNRS, Aix Marseille Université, BIP, IMM, IM2B, 31 Chemin J. Aiguier, 13009, Marseille, France.,Aix Marseille Université, CNRS, Laboratoire de Chimie Bactérienne (UMR7283), IMM, IM2B, 31 Chemin J. Aiguier, 13009, Marseille, France
| | - Marianne Broc
- Aix Marseille Université, CNRS, Laboratoire de Chimie Bactérienne (UMR7283), IMM, IM2B, 31 Chemin J. Aiguier, 13009, Marseille, France
| | - Rita R Manuel
- Instituto de Tecnologia Quimica e Biologica Antonio Xavier (ITQB NOVA), Universidade Nova de Lisboa, Oeiras, Portugal
| | - Axel Magalon
- Aix Marseille Université, CNRS, Laboratoire de Chimie Bactérienne (UMR7283), IMM, IM2B, 31 Chemin J. Aiguier, 13009, Marseille, France
| | - Christophe Léger
- CNRS, Aix Marseille Université, BIP, IMM, IM2B, 31 Chemin J. Aiguier, 13009, Marseille, France
| | - Inês A C Pereira
- Instituto de Tecnologia Quimica e Biologica Antonio Xavier (ITQB NOVA), Universidade Nova de Lisboa, Oeiras, Portugal
| | - Anne Walburger
- Aix Marseille Université, CNRS, Laboratoire de Chimie Bactérienne (UMR7283), IMM, IM2B, 31 Chemin J. Aiguier, 13009, Marseille, France
| | - Vincent Fourmond
- CNRS, Aix Marseille Université, BIP, IMM, IM2B, 31 Chemin J. Aiguier, 13009, Marseille, France
| |
Collapse
|
8
|
Cha J, Bak H, Kwon I. Hydrogen-fueled CO 2 reduction using oxygen-tolerant oxidoreductases. Front Bioeng Biotechnol 2023; 10:1078164. [PMID: 36686231 PMCID: PMC9849572 DOI: 10.3389/fbioe.2022.1078164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 12/22/2022] [Indexed: 01/06/2023] Open
Abstract
Hydrogen gas obtained from cheap or sustainable sources has been investigated as an alternative to fossil fuels. By using hydrogenase (H2ase) and formate dehydrogenase (FDH), H2 and CO2 gases can be converted to formate, which can be conveniently stored and transported. However, developing an enzymatic process that converts H2 and CO2 obtained from cheap sources into formate is challenging because even a very small amount of O2 included in the cheap sources damages most H2ases and FDHs. In order to overcome this limitation, we investigated a pair of oxygen-tolerant H2ase and FDH. We achieved the cascade reaction between H2ase from Ralstonia eutropha H16 (ReSH) and FDH from Rhodobacter capsulatus (RcFDH) to convert H2 and CO2 to formate using in situ regeneration of NAD+/NADH in the presence of O2.
Collapse
Affiliation(s)
- Jaehyun Cha
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Hyeonseon Bak
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea
| | - Inchan Kwon
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea,Research Center for Innovative Energy and Carbon Optimized Synthesis for Chemicals (Inn-ECOSysChem), Gwangju Institute of Science and Technology (GIST), Gwangju, South Korea,*Correspondence: Inchan Kwon,
| |
Collapse
|
9
|
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.
Collapse
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
| |
Collapse
|
10
|
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.
Collapse
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.)
| |
Collapse
|
11
|
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.
Collapse
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
| |
Collapse
|
12
|
Petushkova E, Mayorova E, Tsygankov A. TCA Cycle Replenishing Pathways in Photosynthetic Purple Non-Sulfur Bacteria Growing with Acetate. Life (Basel) 2021; 11:711. [PMID: 34357087 PMCID: PMC8307300 DOI: 10.3390/life11070711] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 06/27/2021] [Accepted: 07/14/2021] [Indexed: 11/23/2022] Open
Abstract
Purple non-sulfur bacteria (PNSB) are anoxygenic photosynthetic bacteria harnessing simple organic acids as electron donors. PNSB produce a-aminolevulinic acid, polyhydroxyalcanoates, bacteriochlorophylls a and b, ubiquinones, and other valuable compounds. They are highly promising producers of molecular hydrogen. PNSB can be cultivated in organic waste waters, such as wastes after fermentation. In most cases, wastes mainly contain acetic acid. Therefore, understanding the anaplerotic pathways in PNSB is crucial for their potential application as producers of biofuels. The present review addresses the recent data on presence and diversity of anaplerotic pathways in PNSB and describes different classifications of these pathways.
Collapse
Affiliation(s)
- Ekaterina Petushkova
- Pushchino Scientific Center for Biological Research, Institute of Basic Biological Problems Russian Academy of Sciences, 2, Institutskaya Str, 142290 Pushchino, Moscow Region, Russia; (E.P.); (E.M.)
| | - Ekaterina Mayorova
- Pushchino Scientific Center for Biological Research, Institute of Basic Biological Problems Russian Academy of Sciences, 2, Institutskaya Str, 142290 Pushchino, Moscow Region, Russia; (E.P.); (E.M.)
- Pushchino State Institute of Natural Science, The Federal State Budget Educational Institution of Higher Education, 3, Prospekt Nauki, 142290 Pushchino, Moscow Region, Russia
| | - Anatoly Tsygankov
- Pushchino Scientific Center for Biological Research, Institute of Basic Biological Problems Russian Academy of Sciences, 2, Institutskaya Str, 142290 Pushchino, Moscow Region, Russia; (E.P.); (E.M.)
| |
Collapse
|
13
|
Molybdenum-Containing Metalloenzymes and Synthetic Catalysts for Conversion of Small Molecules. Catalysts 2021. [DOI: 10.3390/catal11020217] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The energy deficiency and environmental problems have motivated researchers to develop energy conversion systems into a sustainable pathway, and the development of catalysts holds the center of the research endeavors. Natural catalysts such as metalloenzymes have maintained energy cycles on Earth, thus proving themselves the optimal catalysts. In the previous research results, the structural and functional analogs of enzymes and nano-sized electrocatalysts have shown promising activities in energy conversion reactions. Mo ion plays essential roles in natural and artificial catalysts, and the unique electrochemical properties render its versatile utilization as an electrocatalyst. In this review paper, we show the current understandings of the Mo-enzyme active sites and the recent advances in the synthesis of Mo-catalysts aiming for high-performing catalysts.
Collapse
|
14
|
Robinson WE, Bassegoda A, Blaza JN, Reisner E, Hirst J. Understanding How the Rate of C-H Bond Cleavage Affects Formate Oxidation Catalysis by a Mo-Dependent Formate Dehydrogenase. J Am Chem Soc 2020; 142:12226-12236. [PMID: 32551568 PMCID: PMC7366381 DOI: 10.1021/jacs.0c03574] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Metal-dependent formate dehydrogenases (FDHs) catalyze the reversible conversion of formate into CO2, a proton, and two electrons. Kinetic studies of FDHs provide key insights into their mechanism of catalysis, relevant as a guide for the development of efficient electrocatalysts for formate oxidation as well as for CO2 capture and utilization. Here, we identify and explain the kinetic isotope effect (KIE) observed for the oxidation of formate and deuterioformate by the Mo-containing FDH from Escherichia coli using three different techniques: steady-state solution kinetic assays, protein film electrochemistry (PFE), and pre-steady-state stopped-flow methods. For each technique, the Mo center of FDH is reoxidized at a different rate following formate oxidation, significantly affecting the observed kinetic behavior and providing three different viewpoints on the KIE. Steady-state turnover in solution, using an artificial electron acceptor, is kinetically limited by diffusional intermolecular electron transfer, masking the KIE. In contrast, interfacial electron transfer in PFE is fast, lifting the electron-transfer rate limitation and manifesting a KIE of 2.44. Pre-steady-state analyses using stopped-flow spectroscopy revealed a KIE of 3 that can be assigned to the C-H bond cleavage step during formate oxidation. We formalize our understanding of FDH catalysis by fitting all the data to a single kinetic model, recreating the condition-dependent shift in rate-limitation of FDH catalysis between active-site chemical catalysis and regenerative electron transfer. Furthermore, our model predicts the steady-state and time-dependent concentrations of catalytic intermediates, providing a valuable framework for the design of future mechanistic experiments.
Collapse
Affiliation(s)
- William E Robinson
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Arnau Bassegoda
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, U.K
| | - James N Blaza
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, U.K
| | - Erwin Reisner
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, U.K
| | - Judy Hirst
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, U.K
| |
Collapse
|
15
|
Radon C, Mittelstädt G, Duffus BR, Bürger J, Hartmann T, Mielke T, Teutloff C, Leimkühler S, Wendler P. Cryo-EM structures reveal intricate Fe-S cluster arrangement and charging in Rhodobacter capsulatus formate dehydrogenase. Nat Commun 2020; 11:1912. [PMID: 32313256 PMCID: PMC7171172 DOI: 10.1038/s41467-020-15614-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 03/19/2020] [Indexed: 11/09/2022] Open
Abstract
Metal-containing formate dehydrogenases (FDH) catalyse the reversible oxidation of formate to carbon dioxide at their molybdenum or tungsten active site. They display a diverse subunit and cofactor composition, but structural information on these enzymes is limited. Here we report the cryo-electron microscopic structures of the soluble Rhodobacter capsulatus FDH (RcFDH) as isolated and in the presence of reduced nicotinamide adenine dinucleotide (NADH). RcFDH assembles into a 360 kDa dimer of heterotetramers revealing a putative interconnection of electron pathway chains. In the presence of NADH, the RcFDH structure shows charging of cofactors, indicative of an increased electron load. Rhodobacter capsulatus NAD+ dependent formate dehydrogenase (RcFDH) is a molybdoenzyme that catalyses the reversible oxidation of formate to carbon dioxide, and is of interest for biotechnological applications. Here the authors present the cryo-EM structures of RcFDH as isolated from R. capsulatus and in the reduced state with bound NADH, and discuss the enzyme mechanism.
Collapse
Affiliation(s)
- Christin Radon
- Institute of Biochemistry and Biology, Department of Biochemistry, University of Potsdam, Karl-Liebknecht Strasse 24-25, 14476, Potsdam-Golm, Germany
| | - Gerd Mittelstädt
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, Karl-Liebknecht Strasse 24-25, 14476, Potsdam-Golm, Germany.,Ferrier Research Institute, Victoria University of Wellington, Kelburn Parade, Wellington, 6012, New Zealand
| | - Benjamin R Duffus
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, Karl-Liebknecht Strasse 24-25, 14476, Potsdam-Golm, Germany
| | - Jörg Bürger
- Max-Planck Institute of Molecular Genetics, Ihnestrasse 63-73, 14195, Berlin, Germany.,Charité, Institut für Medizinische Physik und Biophysik, Charitéplatz 1, 10117, Berlin, Germany
| | - Tobias Hartmann
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, Karl-Liebknecht Strasse 24-25, 14476, Potsdam-Golm, Germany
| | - Thorsten Mielke
- Max-Planck Institute of Molecular Genetics, Ihnestrasse 63-73, 14195, Berlin, Germany
| | - Christian Teutloff
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195, Berlin, Germany
| | - Silke Leimkühler
- Institute of Biochemistry and Biology, Department of Molecular Enzymology, University of Potsdam, Karl-Liebknecht Strasse 24-25, 14476, Potsdam-Golm, Germany
| | - Petra Wendler
- Institute of Biochemistry and Biology, Department of Biochemistry, University of Potsdam, Karl-Liebknecht Strasse 24-25, 14476, Potsdam-Golm, Germany.
| |
Collapse
|