1
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Yu J, Park MJ, Lee J, Kwon SJ, Lim JK, Lee HS, Kang SG, Lee JH, Kwon KK, Kim YJ. Genomic potential and physiological characteristics of C1 metabolism in novel acetogenic bacteria. Front Microbiol 2023; 14:1279544. [PMID: 37933250 PMCID: PMC10625859 DOI: 10.3389/fmicb.2023.1279544] [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: 08/18/2023] [Accepted: 10/05/2023] [Indexed: 11/08/2023] Open
Abstract
Acetogenic bacteria can utilize C1 compounds, such as carbon monoxide (CO), formate, and methanol, via the Wood-Ljungdahl pathway (WLP) to produce biofuels and biochemicals. Two novel acetogenic bacteria of the family Eubacteriaceae ES2 and ES3 were isolated from Eulsukdo, a delta island in South Korea. We conducted whole genome sequencing of the ES strains and comparative genome analysis on the core clusters of WLP with Acetobacterium woodii DSM1030T and Eubacterium limosum ATCC8486T. The methyl-branch cluster included a formate transporter and duplicates or triplicates copies of the fhs gene, which encodes formyl-tetrahydrofolate synthetase. The formate dehydrogenase cluster did not include the hydrogenase gene, which might be replaced by a functional complex with a separate electron bifurcating hydrogenase (HytABCDE). Additionally, duplicated copies of the acsB gene, encoding acetyl-CoA synthase, are located within or close to the carbonyl-branch cluster. The serum bottle culture showed that ES strains can utilize a diverse range of C1 compounds, including CO, formate, and methanol, as well as CO2. Notably, ES2 exhibited remarkable resistance to high concentrations of C1 substrates, such as 100% CO (200 kPa), 700 mM formate, and 500 mM methanol. Moreover, ES2 demonstrated remarkable growth rates under 50% CO (0.45 h-1) and 200 mM formate (0.34 h-1). These growth rates are comparable to or surpassing those previously reported in other acetogenic bacteria. Our study introduces novel acetogenic ES strains and describes their genetic and physiological characteristics, which can be utilized in C1-based biomanufacturing.
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Affiliation(s)
- Jihyun Yu
- Korea Institute of Ocean Science and Technology, Busan, Republic of Korea
- KIOST School, University of Science and Technology, Daejeon, Republic of Korea
| | - Mi-Jeong Park
- Korea Institute of Ocean Science and Technology, Busan, Republic of Korea
| | - Joungmin Lee
- Korea Institute of Ocean Science and Technology, Busan, Republic of Korea
| | - Soo Jae Kwon
- Korea Institute of Ocean Science and Technology, Busan, Republic of Korea
- KIOST School, University of Science and Technology, Daejeon, Republic of Korea
| | - Jae Kyu Lim
- Korea Institute of Ocean Science and Technology, Busan, Republic of Korea
- KIOST School, University of Science and Technology, Daejeon, Republic of Korea
| | - Hyun Sook Lee
- Korea Institute of Ocean Science and Technology, Busan, Republic of Korea
- KIOST School, University of Science and Technology, Daejeon, Republic of Korea
| | - Sung Gyun Kang
- Korea Institute of Ocean Science and Technology, Busan, Republic of Korea
- KIOST School, University of Science and Technology, Daejeon, Republic of Korea
| | - Jung-Hyun Lee
- Korea Institute of Ocean Science and Technology, Busan, Republic of Korea
- KIOST School, University of Science and Technology, Daejeon, Republic of Korea
| | - Kae Kyoung Kwon
- Korea Institute of Ocean Science and Technology, Busan, Republic of Korea
- KIOST School, University of Science and Technology, Daejeon, Republic of Korea
| | - Yun Jae Kim
- Korea Institute of Ocean Science and Technology, Busan, Republic of Korea
- KIOST School, University of Science and Technology, Daejeon, Republic of Korea
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2
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Hagen WR. The Development of Tungsten Biochemistry-A Personal Recollection. Molecules 2023; 28:molecules28104017. [PMID: 37241758 DOI: 10.3390/molecules28104017] [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: 04/04/2023] [Revised: 04/27/2023] [Accepted: 05/08/2023] [Indexed: 05/28/2023] Open
Abstract
The development of tungsten biochemistry is sketched from the viewpoint of personal participation. Following its identification as a bio-element, a catalogue of genes, enzymes, and reactions was built up. EPR spectroscopic monitoring of redox states was, and remains, a prominent tool in attempts to understand tungstopterin-based catalysis. A paucity of pre-steady-state data remains a hindrance to overcome to this day. Tungstate transport systems have been characterized and found to be very specific for W over Mo. Additional selectivity is presented by the biosynthetic machinery for tungstopterin enzymes. Metallomics analysis of hyperthermophilic archaeon Pyrococcus furiosus indicates a comprehensive inventory of tungsten proteins.
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Affiliation(s)
- Wilfred R Hagen
- Department of Biotechnology, Delft University of Technology, Building 58, Van der Maasweg 9, 2629 HZ Delft, The Netherlands
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3
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Oliveira AR, Mota C, Klymanska K, Biaso F, Romão MJ, Guigliarelli B, Pereira IC. Spectroscopic and Structural Characterization of Reduced Desulfovibrio vulgaris Hildenborough W-FdhAB Reveals Stable Metal Coordination during Catalysis. ACS Chem Biol 2022; 17:1901-1909. [PMID: 35766974 PMCID: PMC9774666 DOI: 10.1021/acschembio.2c00336] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Metal-dependent formate dehydrogenases are important enzymes due to their activity of CO2 reduction to formate. The tungsten-containing FdhAB formate dehydrogenase from Desulfovibrio vulgaris Hildenborough is a good example displaying high activity, simple composition, and a notable structural and catalytic robustness. Here, we report the first spectroscopic redox characterization of FdhAB metal centers by EPR. Titration with dithionite or formate leads to reduction of three [4Fe-4S]1+ clusters, and full reduction requires Ti(III)-citrate. The redox potentials of the four [4Fe-4S]1+ centers range between -250 and -530 mV. Two distinct WV signals were detected, WDV and WFV, which differ in only the g2-value. This difference can be explained by small variations in the twist angle of the two pyranopterins, as determined through DFT calculations of model compounds. The redox potential of WVI/V was determined to be -370 mV when reduced by dithionite and -340 mV when reduced by formate. The crystal structure of dithionite-reduced FdhAB was determined at high resolution (1.5 Å), revealing the same structural alterations as reported for the formate-reduced structure. These results corroborate a stable six-ligand W coordination in the catalytic intermediate WV state of FdhAB.
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Affiliation(s)
- Ana Rita Oliveira
- Instituto
de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Cristiano Mota
- Associate
Laboratory i4HB—Institute for Health and Bioeconomy, NOVA School
of Science and Technology, Universidade
NOVA de Lisboa, 2829-516 Caparica, Portugal,UCIBIO,
Applied Molecular Biosciences Unit, Departament of Chemistry, NOVA
School of Science and Technology, Universidade
NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Kateryna Klymanska
- Associate
Laboratory i4HB—Institute for Health and Bioeconomy, NOVA School
of Science and Technology, Universidade
NOVA de Lisboa, 2829-516 Caparica, Portugal,UCIBIO,
Applied Molecular Biosciences Unit, Departament of Chemistry, NOVA
School of Science and Technology, Universidade
NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Frédéric Biaso
- Laboratoire
de Bioénergétique et Ingénierie des Protéines, Aix Marseille Univ, CNRS, BIP, Marseille 13402, France
| | - Maria João Romão
- Associate
Laboratory i4HB—Institute for Health and Bioeconomy, NOVA School
of Science and Technology, Universidade
NOVA de Lisboa, 2829-516 Caparica, Portugal,UCIBIO,
Applied Molecular Biosciences Unit, Departament of Chemistry, NOVA
School of Science and Technology, Universidade
NOVA de Lisboa, 2829-516 Caparica, Portugal,
| | - Bruno Guigliarelli
- Laboratoire
de Bioénergétique et Ingénierie des Protéines, Aix Marseille Univ, CNRS, BIP, Marseille 13402, France,
| | - Inês Cardoso Pereira
- Instituto
de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal,
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4
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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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5
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Moon J, Dönig J, Kramer S, Poehlein A, Daniel R, Müller V. Formate metabolism in the acetogenic bacterium Acetobacterium woodii. Environ Microbiol 2021; 23:4214-4227. [PMID: 33989450 DOI: 10.1111/1462-2920.15598] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 05/12/2021] [Indexed: 11/29/2022]
Abstract
Acetogenic bacteria are already established as biocatalysts for production of high-value compounds from C1 substrates such as H2 + CO2 or CO. However, little is known about the physiology, biochemistry and bioenergetics of acetogenesis from formate, an interesting feedstock for biorefineries. Here, we analysed formate metabolism in the model acetogen Acetobacterium woodii. Cells grew optimally on 200 mM formate to an optical density of 0.6. Formate was exclusively converted to acetate (and CO2 ) with a ratio of 4.4:1. Transcriptome analyses revealed genes/enzymes involved in formate metabolism. Strikingly, A. woodii has two genes potentially encoding a formyl-THF synthetase, fhs1 and fhs2. fhs2 forms an operon with a gene encoding a potential formate transporter, fdhC. Deletion of fhs2/fdhC led to a reduced growth rate, formate consumption and optical densities. Acetogenesis from H2 + CO2 was accompanied by transient formate production; strikingly, formate reutilization was completely abolished in the Δfhs2/fdhC mutant. Take together, our studies gave the first detailed insights into the formatotrophic lifestyle of A. woodii.
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Affiliation(s)
- Jimyung Moon
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, D-60438, Germany
| | - Judith Dönig
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, D-60438, Germany
| | - Sina Kramer
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, D-60438, Germany
| | - Anja Poehlein
- Göttingen Genomics Laboratory, Institute for Microbiology and Genetics, Georg August University, Grisebachstr. 8, Göttingen, D-37077, Germany
| | - Rolf Daniel
- Göttingen Genomics Laboratory, Institute for Microbiology and Genetics, Georg August University, Grisebachstr. 8, Göttingen, D-37077, Germany
| | - Volker Müller
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University, Max-von-Laue Str. 9, Frankfurt, D-60438, Germany
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6
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Maia LB, Moura I, Moura JJ. Molybdenum and tungsten-containing formate dehydrogenases: Aiming to inspire a catalyst for carbon dioxide utilization. Inorganica Chim Acta 2017. [DOI: 10.1016/j.ica.2016.07.010] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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7
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Molybdenum and tungsten-dependent formate dehydrogenases. J Biol Inorg Chem 2014; 20:287-309. [DOI: 10.1007/s00775-014-1218-2] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Accepted: 11/09/2014] [Indexed: 11/25/2022]
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8
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Schulzke C. Temperature dependent electrochemical investigations of molybdenum and tungsten oxobisdithiolene complexes. Dalton Trans 2005:713-20. [PMID: 15702182 DOI: 10.1039/b414853c] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To achieve a better understanding why thermophilic and hyperthermophilic organisms use tungsten instead of molybdenum within the active sites of their molybdopterin dependent oxidases, electrochemical investigations of model complexes for the active sites of enzymes belonging to the DMSO reductase (molybdenum) and the aldehyde oxidoreductase (tungsten) family have been undertaken. Cyclic voltammetry and differential pulse voltammetry of four pairs of molybdenum and tungsten oxobisdithiolene compounds show huge differences in the response of their redox potentials to rising or decreasing temperatures, depending on the substituents at the dithiolene group. The mnt2- compounds (1a, 1b) respond with decreasing redox potentials E(1/2) to rising temperatures whereas all other compounds show positive gradients deltaE/deltaT. In every case the values for the gradients for the tungsten compounds are greater than those for the molybdenum compounds. Six of the investigated compounds are known in the literature and two compounds were newly synthesized. These two new compounds include the pyrane subunit of the native molybdopterin ligand and should therefore be even better models for the active site of the molybdopterin containing enzymes. The molybdenum/tungsten pair with these new ligands shows a remarkably small difference for the redox potentials of the transition M(IV) <--> M(V) of only 30 mV at 25 degrees C and the reversion of the usual order with higher potentials for the molybdenum than the tungsten compound at a temperature of 70 degrees C; a temperature that is in the range where usually tungsten containing enzymes instead of molybdenum containing ones are found.
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Affiliation(s)
- Carola Schulzke
- Institut für Anorganische Chemie, Universität Göttingen, 37077 Göttingen, Germany.
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9
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Brondino CD, Passeggi MCG, Caldeira J, Almendra MJ, Feio MJ, Moura JJG, Moura I. Incorporation of either molybdenum or tungsten into formate dehydrogenase from Desulfovibrio alaskensis NCIMB 13491; EPR assignment of the proximal iron-sulfur cluster to the pterin cofactor in formate dehydrogenases from sulfate-reducing bacteria. J Biol Inorg Chem 2003; 9:145-51. [PMID: 14669076 DOI: 10.1007/s00775-003-0506-z] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2003] [Accepted: 10/24/2003] [Indexed: 10/26/2022]
Abstract
We report the characterization of the molecular properties and EPR studies of a new formate dehydrogenase (FDH) from the sulfate-reducing organism Desulfovibrio alaskensis NCIMB 13491. FDHs are enzymes that catalyze the two-electron oxidation of formate to carbon dioxide in several aerobic and anaerobic organisms. D. alaskensis FDH is a heterodimeric protein with a molecular weight of 126+/-2 kDa composed of two subunits, alpha=93+/-3 kDa and beta=32+/-2 kDa, which contains 6+/-1 Fe/molecule, 0.4+/-0.1 Mo/molecule, 0.3+/-0.1 W/molecule, and 1.3+/-0.1 guanine monophosphate nucleotides. The UV-vis absorption spectrum of D. alaskensis FDH is typical of an iron-sulfur protein with a broad band around 400 nm. Variable-temperature EPR studies performed on reduced samples of D. alaskensis FDH showed the presence of signals associated with the different paramagnetic centers of D. alaskensis FDH. Three rhombic signals having g-values and relaxation behavior characteristic of [4Fe-4S] clusters were observed in the 5-40 K temperature range. Two EPR signals with all the g-values less than two, which accounted for less than 0.1 spin/protein, typical of mononuclear Mo(V) and W(V), respectively, were observed. The signal associated with the W(V) ion has a larger deviation from the free electron g-value, as expected for tungsten in a d(1) configuration, albeit with an unusual relaxation behavior. The EPR parameters of the Mo(V) signal are within the range of values typically found for the slow-type signal observed in several Mo-containing proteins belonging to the xanthine oxidase family of enzymes. Mo(V) resonances are split at temperatures below 50 K by magnetic coupling with one of the Fe/S clusters. The analysis of the inter-center magnetic interaction allowed us to assign the EPR-distinguishable iron-sulfur clusters with those seen in the crystal structure of a homologous enzyme.
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Affiliation(s)
- Carlos D Brondino
- REQUIMTE, Departamento de Química, Centro de Química Fisica e Biotecnologia, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal
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10
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de Bok FAM, Hagedoorn PL, Silva PJ, Hagen WR, Schiltz E, Fritsche K, Stams AJM. Two W-containing formate dehydrogenases (CO2-reductases) involved in syntrophic propionate oxidation by Syntrophobacter fumaroxidans. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:2476-85. [PMID: 12755703 DOI: 10.1046/j.1432-1033.2003.03619.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Two formate dehydrogenases (CO2-reductases) (FDH-1 and FDH-2) were isolated from the syntrophic propionate-oxidizing bacterium Syntrophobacter fumaroxidans. Both enzymes were produced in axenic fumarate-grown cells as well as in cells which were grown syntrophically on propionate with Methanospirillum hungatei as the H2 and formate scavenger. The purified enzymes exhibited extremely high formate-oxidation and CO2-reduction rates, and low Km values for formate. For the enzyme designated FDH-1, a specific formate oxidation rate of 700 U.mg-1 and a Km for formate of 0.04 mm were measured when benzyl viologen was used as an artificial electron acceptor. The enzyme designated FDH-2 oxidized formate with a specific activity of 2700 U.mg-1 and a Km of 0.01 mm for formate with benzyl viologen as electron acceptor. The specific CO2-reduction (to formate) rates measured for FDH-1 and FDH-2, using dithionite-reduced methyl viologen as the electron donor, were 900 U.mg-1 and 89 U.mg-1, respectively. From gel filtration and polyacrylamide gel electrophoresis it was concluded that FDH-1 is composed of three subunits (89 +/- 3, 56 +/- 2 and 19 +/- 1 kDa) and has a native molecular mass of approximately 350 kDa. FDH-2 appeared to be a heterodimer composed of a 92 +/- 3 kDa and a 33 +/- 2 kDa subunit. Both enzymes contained tungsten and selenium, while molybdenum was not detected. EPR spectroscopy suggested that FDH-1 contains at least four [2Fe-2S] clusters per molecule and additionally paramagnetically coupled [4Fe-4S] clusters. FDH-2 contains at least two [4Fe-4S] clusters per molecule. As both enzymes are produced under all growth conditions tested, but with differences in levels, expression may depend on unknown parameters.
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Affiliation(s)
- Frank A M de Bok
- Laboratory of Microbiology, Wageningen University, The Netherlands.
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11
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Dhawan IK, Roy R, Koehler BP, Mukund S, Adams MW, Johnson MK. Spectroscopic studies of the tungsten-containing formaldehyde ferredoxin oxidoreductase from the hyperthermophilic archaeon Thermococcus litoralis. J Biol Inorg Chem 2000; 5:313-27. [PMID: 10907742 DOI: 10.1007/pl00010660] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The electronic and redox properties of the iron-sulfur cluster and tungsten center in the as-isolated and sulfide-activated forms of formaldehyde ferredoxin oxidoreductase (FOR) from Thermococcus litoralis (Tl) have been investigated by using the combination of EPR and variable-temperature magnetic circular dichroism (VTMCD) spectroscopies. The results reveal a [Fe4S4]2+,+ cluster (Em=-368mV) that undergoes redox cycling between an oxidized form with an S=0 ground state and a reduced form that exists as a pH- and medium-dependent mixture of S=3/2 (g=5.4; E/D=0.33) and S=1/2 (g=2.03, 1.93, 1.86) ground states, with the former dominating in the presence of 50% (v/v) glycerol. Three distinct types of W(V) EPR signals have been observed during dye-mediated redox titration of as-isolated Tl FOR. The initial resonance observed upon oxidation, termed the "low-potential" W(V) species (g=1.977, 1.898, 1.843), corresponds to approximately 25-30% of the total W and undergoes redox cycling between W(IV)/ W(V) and W(V)/W(VI) states at physiologically relevant potentials (Em= -335 and -280 mV, respectively). At higher potentials a minor "mid-potential" W(V) species, g= 1.983, 1.956, 1.932, accounting for less than 5 % of the total W, appears with a midpoint potential of -34 mV and persists up to at least + 300 mV. At potentials above 0 mV, a major "high-potential" W(V) signal, g= 1.981, 1.956, 1.883, accounting for 30-40% of the total W, appears at a midpoint potential of +184 mV. As-isolated samples of Tl FOR were found to undergo an approximately 8-fold enhancement in activity on incubation with excess Na2S under reducing conditions and the sulfide-activated Tl FOR was partially inactivated by cyanide. The spectroscopic and redox properties of the sulfide-activated Tl FOR are quite distinct from those of the as-isolated enzyme, with loss of the low-potential species and changes in both the mid-potential W(V) species (g= 1.981, 1.950, 1.931; Em = -265 mV) and high-potential W(V) species (g=1.981, 1.952, 1.895; Em = +65 mV). Taken together, the W(V) species in sulfide-activated samples of Tl FOR maximally account for only 15% of the total W. Both types of high-potential W(V) species were lost upon incubation with cyanide and the sulfide-activated high-potential species is converted into the as-isolated high-potential species upon exposure to air. Structural models are proposed for each of the observed W(V) species and both types of mid-potential and high-potential species are proposed to be artifacts of ligand-based oxidation of W(VI) species. A W(VI) species with terminal sulfido or thiol ligands is proposed to be responsible for the catalytic activity in sulfide-activated samples of Tl FOR.
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Affiliation(s)
- I K Dhawan
- Department of Biochemistry & Molecular Biology and Center for Metalloenzyme Studies, University of Georgia, Athens 30602, USA
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12
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Kengen SW, Rikken GB, Hagen WR, van Ginkel CG, Stams AJ. Purification and characterization of (per)chlorate reductase from the chlorate-respiring strain GR-1. J Bacteriol 1999; 181:6706-11. [PMID: 10542172 PMCID: PMC94135 DOI: 10.1128/jb.181.21.6706-6711.1999] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Strain GR-1 is one of several recently isolated bacterial species that are able to respire by using chlorate or perchlorate as the terminal electron acceptor. The organism performs a complete reduction of chlorate or perchlorate to chloride and oxygen, with the intermediate formation of chlorite. This study describes the purification and characterization of the key enzyme of the reductive pathway, the chlorate and perchlorate reductase. A single enzyme was found to catalyze both the chlorate- and perchlorate-reducing activity. The oxygen-sensitive enzyme was located in the periplasm and had an apparent molecular mass of 420 kDa, with subunits of 95 and 40 kDa in an alpha(3)beta(3) composition. Metal analysis showed the presence of 11 mol of iron, 1 mol of molybdenum, and 1 mol of selenium per mol of heterodimer. In accordance, quantitative electron paramagnetic resonance spectroscopy showed the presence of one [3Fe-4S] cluster and two [4Fe-4S] clusters. Furthermore, two different signals were ascribed to Mo(V). The K(m) values for perchlorate and chlorate were 27 and <5 microM, respectively. Besides perchlorate and chlorate, nitrate, iodate, and bromate were also reduced at considerable rates. The resemblance of the enzyme to nitrate reductases, formate dehydrogenases, and selenate reductase is discussed.
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Affiliation(s)
- S W Kengen
- Laboratory of Microbiology, Department of Biomolecular Sciences, Wageningen Agricultural University, NL-6703 CT Wageningen, The Netherlands.
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Barnard KR, Bruck M, Huber S, Grittini C, Enemark JH, Gable RW, Wedd AG. Mononuclear and Binuclear Molybdenum(V) Complexes of the Ligand N,N‘-Dimethyl-N,N‘-bis(2-mercaptophenyl)ethylenediamine: Geometric Isomers. Inorg Chem 1997. [DOI: 10.1021/ic960848h] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Keith R. Barnard
- School of Chemistry, University of Melbourne, Parkville, Victoria 3052, Australia, and Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Michael Bruck
- School of Chemistry, University of Melbourne, Parkville, Victoria 3052, Australia, and Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Susan Huber
- School of Chemistry, University of Melbourne, Parkville, Victoria 3052, Australia, and Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Carina Grittini
- School of Chemistry, University of Melbourne, Parkville, Victoria 3052, Australia, and Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - John H. Enemark
- School of Chemistry, University of Melbourne, Parkville, Victoria 3052, Australia, and Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Robert W. Gable
- School of Chemistry, University of Melbourne, Parkville, Victoria 3052, Australia, and Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Anthony G. Wedd
- School of Chemistry, University of Melbourne, Parkville, Victoria 3052, Australia, and Department of Chemistry, University of Arizona, Tucson, Arizona 85721
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Koehler BP, Mukund S, Conover RC, Dhawan IK, Roy R, Adams MWW, Johnson MK. Spectroscopic Characterization of the Tungsten and Iron Centers in Aldehyde Ferredoxin Oxidoreductases from Two Hyperthermophilic Archaea. J Am Chem Soc 1996. [DOI: 10.1021/ja962197u] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Brian P. Koehler
- Contribution from the Departments of Chemistry and Biochemistry and the Center for Metalloenzyme Studies, University of Georgia, Athens, Georgia 30602
| | - Swarnalatha Mukund
- Contribution from the Departments of Chemistry and Biochemistry and the Center for Metalloenzyme Studies, University of Georgia, Athens, Georgia 30602
| | - Richard C. Conover
- Contribution from the Departments of Chemistry and Biochemistry and the Center for Metalloenzyme Studies, University of Georgia, Athens, Georgia 30602
| | - Ish K. Dhawan
- Contribution from the Departments of Chemistry and Biochemistry and the Center for Metalloenzyme Studies, University of Georgia, Athens, Georgia 30602
| | - Roopali Roy
- Contribution from the Departments of Chemistry and Biochemistry and the Center for Metalloenzyme Studies, University of Georgia, Athens, Georgia 30602
| | - Michael W. W. Adams
- Contribution from the Departments of Chemistry and Biochemistry and the Center for Metalloenzyme Studies, University of Georgia, Athens, Georgia 30602
| | - Michael K. Johnson
- Contribution from the Departments of Chemistry and Biochemistry and the Center for Metalloenzyme Studies, University of Georgia, Athens, Georgia 30602
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Oku H, Ueyama N, Nakamura A. Benzoin Oxidation at Extreme Temperature by Bis (1,2-benzenedithiolato)dioxotungstate(VI) Complex: A Model Study for Hyperthermostable Tungsten Oxidoreductases. CHEM LETT 1996. [DOI: 10.1246/cl.1996.1131] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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17
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Affiliation(s)
- Michael K. Johnson
- Department of Chemistry and Department of Biochemistry & Molecular Biology, and Center for Metalloenzyme Studies, University of Georgia, Athens, Georgia 30602, and Division of Chemistry, California Institute of Technology, Pasadena, California 91125
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Oku H, Ueyama N, Nakamura A. Stabilization of Oxo-Metal Bonding by the π-Conjugated System in Dithiolate Ligands:cis-Dioxotungsten(VI) Bis(naphthalenedithiolato) and the Related Complexes as Models for Tungsten Oxidoreductases. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1996. [DOI: 10.1246/bcsj.69.3139] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Dhawan IK, Enemark JH. EPR Studies of Oxo-Molybdenum(V) Complexes with Sulfur Donor Ligands: Implications for the Molybdenum Center of Sulfite Oxidase. Inorg Chem 1996; 35:4873-4882. [PMID: 11666687 DOI: 10.1021/ic9605276] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of six-coordinate compounds containing a chelating dithiolate coordinated to the [LMo(V)O](2+) unit (L = hydrotris(3,5-dimethyl-1-pyrazolyl)borate) have been characterized by EPR spectroscopy as models for the molybdenum centers of pterin-containing molybdenum enzymes. The structure of LMoO(bdt) (1) (bdt = 1,2-benzenedithiolate) has been determined by X-ray crystallography; the space group is P2(1)/n with a = 10.727(1) Å, b = 14.673(2) Å, c = 15.887(2) Å, beta = 100.317(4) degrees and Z = 4. Compound 1 exhibits distorted octahedral stereochemistry; the terminal oxo group and the sulfur atoms are mutually cis to one another. The Mo=O distance is 1.678(4) Å, and the average Mo-S distance is 2.373(2) Å. The EPR parameters for 1, determined from simulation of the frozen-solution spectrum, are g(1) = 2.004, g(2) = 1.972, g(3) = 1.934 and A(1)((95,97)Mo) = 50.0 x 10(-)(4), A(2) = 11.4 x 10(-)(4), A(3) = 49.7 x 10(-)(4) cm(-)(1). The EPR parameters for several LMo(V)O{S(CH(2))(x)()S} compounds (x = 2-4) with saturated chelate skeletons are similar to those of 1, indicating that it is the coordinated S atoms and not unsaturation of the chelate skeleton that gives rise to the large g values for 1. The presence of g components larger than the free-electron value is ascribed to low-energy charge transfer transitions from the filled sulfur pi orbitals to half-filled Mo d orbitals. The EPR spectrum of [LMo(V)O{S(2)P(OEt)(2)}](+) shows an unusually large isotropic (31)P hyperfine splitting of 66.1 x 10(-)(4) cm(-)(1) from the noncoordinated phosphorus atom. The frozen-solution EPR spectra of the low-pH and high-pH forms of sulfite oxidase have been reinvestigated in D(2)O and the anisotropic g and A((95,97)Mo) parameters determined by simulation of the spectrum arising from the naturally abundant Mo isotopes (75% I = 0, 25% I = (5)/(2)). The EPR parameters for the low-pH form are g(1) = 2.007, g(2) = 1.974, g(3) = 1.968 and A(1) = 56.7 x 10(-)(4), A(2) = 25.0 x 10(-)(4), A(3) = 16.7 x 10(-)(4) cm(-)(1). The EPR parameters for the high-pH form are g(1) = 1.990, g(2) = 1.966, g(3) = 1.954 and A(1) = 54.4 x 10(-)(4), A(2) = 21.0 x 10(-)(4), A(3) = 11.3 x 10(-)(4) cm(-)(1). These are the first determinations of the complete A((95,97)Mo) hyperfine components for an enzyme that possesses an [Mo(VI)O(2)](2+) core in its fully oxidized state.
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Affiliation(s)
- Ish K. Dhawan
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
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Adams MW, Kletzin A. Oxidoreductase-type enzymes and redox proteins involved in fermentative metabolisms of hyperthermophilic Archaea. ADVANCES IN PROTEIN CHEMISTRY 1996; 48:101-80. [PMID: 8791625 DOI: 10.1016/s0065-3233(08)60362-9] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- M W Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens 30602, USA
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Hensgens CM, Hagen WR, Hansen TA. Purification and characterization of a benzylviologen-linked, tungsten-containing aldehyde oxidoreductase from Desulfovibrio gigas. J Bacteriol 1995; 177:6195-200. [PMID: 7592385 PMCID: PMC177460 DOI: 10.1128/jb.177.21.6195-6200.1995] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Desulfovibrio gigas NCIMB 9332 cells grown in ethanol-containing medium with 0.1 microM tungstate contained a benzylviologen-linked aldehyde oxidoreductase. The enzyme was purified to electrophoretic homogeneity and found to be a homodimer with a subunit M(r) of 62,000. It contained 0.68 +/- 0.08 W, 4.8 Fe, and 3.2 +/- 0.2 labile S per subunit. After acid iodine oxidation of the purified enzyme, a fluorescence spectrum typical for form A of molybdopterin was obtained. Acetaldehyde, propionaldehyde, and benzaldehyde were excellent substrates, with apparent Km values of 12.5, 10.8, and 20 microM, respectively. The natural electron acceptor is not yet known; benzylviologen was used as an artificial electron acceptor (apparent Km, 0.55 mM). The enzyme was activated by potassium ions and strongly inhibited by cyanide, arsenite, and iodoacetate. In the as-isolated enzyme, electron paramagnetic resonance studies readily detected W(V) as a complex signal with g values in the range of 1.84 to 1.97. The dithionite-reduced enzyme exhibited a broad signal at low temperature with g = 2.04 and 1.92; this is indicative of a [4Fe-4S]1+ cluster interacting with a second paramagnet, possibly the S = 1 system of W(IV). Until now W-containing aldehyde oxidoreductases had only been found in two Clostridium strains and two hyperthermophilic archaea. The D. gigas enzyme is the first example of such an enzyme in a gram-negative bacterium.
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Affiliation(s)
- C M Hensgens
- Department of Microbiology, University of Groningen, The Netherlands
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Rosner BM, Schink B. Purification and characterization of acetylene hydratase of Pelobacter acetylenicus, a tungsten iron-sulfur protein. J Bacteriol 1995; 177:5767-72. [PMID: 7592321 PMCID: PMC177396 DOI: 10.1128/jb.177.20.5767-5772.1995] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Acetylene hydratase of the mesophilic fermenting bacterium Pelobacter acetylenicus catalyzes the hydration of acetylene to acetaldehyde. Growth of P. acetylenicus with acetylene and specific acetylene hydratase activity depended on tungstate or, to a lower degree, molybdate supply in the medium. The specific enzyme activity in cell extract was highest after growth in the presence of tungstate. Enzyme activity was stable even after prolonged storage of the cell extract or of the purified protein under air. However, enzyme activity could be measured only in the presence of a strong reducing agent such as titanium(III) citrate or dithionite. The enzyme was purified 240-fold by ammonium sulfate precipitation, anion-exchange chromatography, size exclusion chromatography, and a second anion-exchange chromatography step, with a yield of 36%. The protein was a monomer with an apparent molecular mass of 73 kDa, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric point was at pH 4.2. Per mol of enzyme, 4.8 mol of iron, 3.9 mol of acid-labile sulfur, and 0.4 mol of tungsten, but no molybdenum, were detected. The Km for acetylene as assayed in a coupled photometric test with yeast alcohol dehydrogenase and NADH was 14 microM, and the Vmax was 69 mumol.min-1.mg of protein-1. The optimum temperature for activity was 50 degrees C, and the apparent pH optimum was 6.0 to 6.5. The N-terminal amino acid sequence gave no indication of resemblance to any enzyme protein described so far.
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Affiliation(s)
- B M Rosner
- Fakultät für Biologie, Universität Konstanz, Constance, Germany
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Rothery RA, Grant JL, Johnson JL, Rajagopalan KV, Weiner JH. Association of molybdopterin guanine dinucleotide with Escherichia coli dimethyl sulfoxide reductase: effect of tungstate and a mob mutation. J Bacteriol 1995; 177:2057-63. [PMID: 7721698 PMCID: PMC176849 DOI: 10.1128/jb.177.8.2057-2063.1995] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We have identified the organic component of the molybdenum cofactor in Escherichia coli dimethyl sulfoxide reductase (DmsABC) to be molybdopterin (MPT) guanine dinucleotide (MGD) and have studied the effects of tungstate and a mob mutation on cofactor (Mo-MGD) insertion. Tungstate severely inhibits anaerobic growth of E. coli on a glycerol-dimethyl sulfoxide minimal medium, and this inhibition is partially overcome by overexpression of DmsABC. Isolation and characterization of an oxidized derivative of MGD (form A) from DmsABC overexpressed in cells grown in the presence of molybdate or tungstate indicate that tungstate inhibits insertion of Mo-MGD. No electron paramagnetic resonance evidence for the assembly of tungsten into DmsABC was found between Eh = -450 mV and Eh = +200 mV. The E. coli mob locus is responsible for the addition of a guanine nucleotide to molybdo-MPT (Mo-MPT) to form Mo-MGD. DmsABC does not bind Mo-MPT or Mo-MGD in a mob mutant, indicating that nucleotide addition must precede cofactor insertion. No electron paramagnetic resonance evidence for the assembly of molybdenum into DmsABC in a mob mutant was found between Eh = -450 mV and Eh = +200 mV. These data support a model for Mo-MGD biosynthesis and assembly into DmsABC in which both metal chelation and nucleotide addition to MPT precede cofactor insertion.
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Affiliation(s)
- R A Rothery
- Department of Biochemistry, University of Alberta, Edmonton, Canada
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25
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Enemark JH, Young CG. Bioinorganic Chemistry of Pterin-Containing Molybdenum and Tungsten Enzymes. ADVANCES IN INORGANIC CHEMISTRY 1993. [DOI: 10.1016/s0898-8838(08)60181-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Schmitz RA, Albracht SP, Thauer RK. Properties of the tungsten-substituted molybdenum formylmethanofuran dehydrogenase from Methanobacterium wolfei. FEBS Lett 1992; 309:78-81. [PMID: 1324851 DOI: 10.1016/0014-5793(92)80743-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In Methanobacterium wolfei two formylmethanofuran dehydrogenases are present, one of which is a molybdenum- and the other a tungsten enzyme. We report here that also the 'molybdenum' enzyme contained tungsten when the archaeon was grown on molybdenum-deprived medium supplemented with tungstate (1 microM). Unexpectedly the tungsten-substituted molybdenum enzyme was catalytically active and displayed a rhombic EPR signal which was attributed to tungsten by the characteristic 183W splitting.
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Affiliation(s)
- R A Schmitz
- Laboratorium für Mikrobiologie, Fachbereichs Biologie, Phillipps-Universität, Marburg, Germany
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Cammack R. Iron—Sulfur Clusters in Enzymes: Themes and Variations. ADVANCES IN INORGANIC CHEMISTRY 1992. [DOI: 10.1016/s0898-8838(08)60066-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Jollie D, Lipscomb J. Formate dehydrogenase from Methylosinus trichosporium OB3b. Purification and spectroscopic characterization of the cofactors. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)54716-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Characterization of a tungsten-iron-sulfur protein exhibiting novel spectroscopic and redox properties from the hyperthermophilic archaebacterium Pyrococcus furiosus. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)38426-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Corbin JL, Watt GD. A chemical preparation of pure reduced viologens for use as biomolecular reducing reagents. Anal Biochem 1990; 186:86-9. [PMID: 2356972 DOI: 10.1016/0003-2697(90)90577-v] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A chemical method is reported for conveniently preparing a variety of pure, reduced low-potential viologens for use as biomolecular reductants. The free radical, semiquinone viologen form is prepared anaerobically in aqueous solution by coproportionation of the dihydroviologen with the fully oxidized viologen according to the following reaction, using methyl viologen (MV) as an example: MV + MVH2 = 2 MV.. By varying the substituents on the viologen nitrogen atoms, a series of viologens of varying charge and reduction potential is easily obtained. Applications involving the reduction of various metalloproteins are presented.
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Affiliation(s)
- J L Corbin
- Department of Chemistry and Biochemistry, University of Colorado, Boulder 80309
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