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Salusjärvi L, Ojala L, Peddinti G, Lienemann M, Jouhten P, Pitkänen JP, Toivari M. Production of biopolymer precursors beta-alanine and L-lactic acid from CO2 with metabolically versatile Rhodococcus opacus DSM 43205. Front Bioeng Biotechnol 2022; 10:989481. [PMID: 36281430 PMCID: PMC9587121 DOI: 10.3389/fbioe.2022.989481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 09/16/2022] [Indexed: 11/18/2022] Open
Abstract
Hydrogen oxidizing autotrophic bacteria are promising hosts for conversion of CO2 into chemicals. In this work, we engineered the metabolically versatile lithoautotrophic bacterium R. opacus strain DSM 43205 for synthesis of polymer precursors. Aspartate decarboxylase (panD) or lactate dehydrogenase (ldh) were expressed for beta-alanine or L-lactic acid production, respectively. The heterotrophic cultivations on glucose produced 25 mg L−1 beta-alanine and 742 mg L−1 L-lactic acid, while autotrophic cultivations with CO2, H2, and O2 resulted in the production of 1.8 mg L−1 beta-alanine and 146 mg L−1 L-lactic acid. Beta-alanine was also produced at 345 μg L−1 from CO2 in electrobioreactors, where H2 and O2 were provided by water electrolysis. This work demonstrates that R. opacus DSM 43205 can be engineered to produce chemicals from CO2 and provides a base for its further metabolic engineering.
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Affiliation(s)
- Laura Salusjärvi
- VTT Technical Research Centre of Finland Ltd., Espoo, Finland
- *Correspondence: Laura Salusjärvi,
| | - Leo Ojala
- VTT Technical Research Centre of Finland Ltd., Espoo, Finland
| | - Gopal Peddinti
- VTT Technical Research Centre of Finland Ltd., Espoo, Finland
| | | | - Paula Jouhten
- Department of Bioproducts and Biosystems, Aalto University, Espoo, Finland
| | | | - Mervi Toivari
- VTT Technical Research Centre of Finland Ltd., Espoo, Finland
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Lee JH, Fredrickson JK, Plymale AE, Dohnalkova AC, Resch CT, McKinley JP, Shi L. An autotrophic H2 -oxidizing, nitrate-respiring, Tc(VII)-reducing Acidovorax sp. isolated from a subsurface oxic-anoxic transition zone. ENVIRONMENTAL MICROBIOLOGY REPORTS 2015; 7:395-403. [PMID: 25558059 DOI: 10.1111/1758-2229.12263] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 12/19/2014] [Indexed: 06/04/2023]
Abstract
Increasing concentrations of H2 with depth were observed across a geologic unconformity and associated redox transition zone in the subsurface at the Hanford Site in south-central Washington, USA. An opposing gradient characterized by decreasing O2 and nitrate concentrations was consistent with microbial-catalysed biogeochemical processes. Sterile sand was incubated in situ within a multilevel sampler placed across the redox transition zone to evaluate the potential for Tc(VII) reduction and for enrichment of H2 -oxidizing denitrifiers capable of reducing Tc(VII). H2 -driven TcO4 (-) reduction was detected in sand incubated at all depths but was strongest in material from a depth of 17.1 m. Acidovorax spp. were isolated from H2 -nitrate enrichments from colonized sand from 15.1 m, with one representative, strain JHL-9, subsequently characterized. JHL-9 grew on acetate with either O2 or nitrate as electron acceptor (data not shown) and on medium with bicarbonate, H2 and nitrate. JHL-9 also reduced pertechnetate (TcO4 (-) ) under denitrifying conditions with H2 as the electron donor. H2 -oxidizing Acidovorax spp. in the subsurface at Hanford and other locations may contribute to the maintenance of subsurface redox gradients and offer the potential for Tc(VII) reduction.
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Affiliation(s)
- Ji-Hoon Lee
- Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | | | | | | | - Charles T Resch
- Pacific Northwest National Laboratory, Richland, WA, 99352, USA
| | | | - Liang Shi
- Pacific Northwest National Laboratory, Richland, WA, 99352, USA
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van der Linden E, Burgdorf T, de Lacey AL, Buhrke T, Scholte M, Fernandez VM, Friedrich B, Albracht SPJ. An improved purification procedure for the soluble [NiFe]-hydrogenase of Ralstonia eutropha: new insights into its (in)stability and spectroscopic properties. J Biol Inorg Chem 2006; 11:247-60. [PMID: 16418856 DOI: 10.1007/s00775-005-0075-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2005] [Accepted: 12/12/2005] [Indexed: 11/28/2022]
Abstract
Infrared (IR) spectra in combination with chemical analyses have recently shown that the active Ni-Fe site of the soluble NAD(+)-reducing [NiFe]-hydrogenase from Ralstonia eutropha contains four cyanide groups and one carbon monoxide as ligands. Experiments presented here confirm this result, but show that a variable percentage of enzyme molecules loses one or two of the cyanide ligands from the active site during routine purification. For this reason the redox conditions during the purification have been optimized yielding hexameric enzyme preparations (HoxFUYHI(2)) with aerobic specific H(2)-NAD(+) activities of 150-185 mumol/min/mg of protein (up to 200% of the highest activity previously reported in the literature). The preparations were highly homogeneous in terms of the active site composition and showed superior IR spectra. IR spectro-electrochemical studies were consistent with the hypothesis that only reoxidation of the reduced enzyme with dioxygen leads to the inactive state, where it is believed that a peroxide group is bound to nickel. Electron paramagnetic resonance experiments showed that the radical signal from the NADH-reduced enzyme derives from the semiquinone form of the flavin (FMN-a) in the hydrogenase module (HoxYH dimer), but not of the flavin (FMN-b) in the NADH-dehydrogenase module (HoxFU dimer). It is further demonstrated that the hexameric enzyme remains active in the presence of NADPH and air, whereas NADH and air lead to rapid destruction of enzyme activity. It is proposed that the presence of NADPH in cells keeps the enzyme in the active state.
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Affiliation(s)
- Eddy van der Linden
- Swammerdam Institute for Life Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, The Netherlands
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Momoshima N, Kakiuchi H. Development of a New Detritiation System Using Microorganisms. FUSION SCIENCE AND TECHNOLOGY 2002. [DOI: 10.13182/fst02-a22620] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Noriyuki Momoshima
- Faculty of Science, Kumamoto University Kurokami, Kumamoto, 860-8555 Japan
| | - Hideki Kakiuchi
- Institute for Environmental Sciences Ienomae, Obuchi, Rokkasho Village, Aomori, 039-3212 Japan
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Bardischewsky F, Friedrich CG. The shxVW locus is essential for oxidation of inorganic sulfur and molecular hydrogen by Paracoccus pantotrophus GB17: a novel function for lithotrophy. FEMS Microbiol Lett 2001; 202:215-20. [PMID: 11520617 DOI: 10.1111/j.1574-6968.2001.tb10806.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The shxVW genes of Paracoccus pantotrophus were identified to be essential for lithotrophic oxidation of sulfur and hydrogen. shxV predicts a membrane protein which is 42% identical to CcdA of P. pantotrophus essential for cytochrome c biogenesis. shxW predicts a periplasmic thioredoxin. Disruption of shxV by an Omega-kanamycin interposon disabled the resulting mutant GB(Omega)V to grow with thiosulfate or molecular hydrogen and to express ShxW while cytochrome c formation was not affected. Mixotrophic growth with succinate and thiosulfate of strain GB(Omega)V revealed 2% of the thiosulfate-dependent oxygen uptake rate as compared to the wild-type while antigens of proteins essential for sulfur oxidation were present in both strains. Mixotrophic growth of strain GB(Omega)V with succinate and molecular hydrogen revealed neither hydrogenase activity nor antigens. Complementation analysis with plasmid pBHP6 carrying the shxVW genes revealed the wild-type phenotype of strain GB(Omega)V(pBHP6).
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Affiliation(s)
- F Bardischewsky
- Lehrstuhl für Technische Mikrobiologie, Fachbereich Chemietechnik, Universität Dortmund, D-44221 Dortmund, Germany
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Abstract
Production of hydrogen by anaerobes, facultative anaerobes, aerobes, methylotrophs, and photosynthetic bacteria is possible. Anaerobic Clostridia are potential producers and immobilized C. butyricum produces 2 mol H2/mol glucose at 50% efficiency. Spontaneous production of H2 from formate and glucose by immobilized Escherichia coli showed 100% and 60% efficiencies, respectively. Enterobactericiae produces H2 at similar efficiency from different monosaccharides during growth. Among methylotrophs, methanogenes, rumen bacteria, and thermophilic archae, Ruminococcus albus, is promising (2.37 mol/mol glucose). Immobilized aerobic Bacillus licheniformis optimally produces 0.7 mol H2/mol glucose. Photosynthetic Rhodospirillum rubrum produces 4, 7, and 6 mol of H2 from acetate, succinate, and malate, respectively. Excellent productivity (6.2 mol H2/mol glucose) by co-cultures of Cellulomonas with a hydrogenase uptake (Hup) mutant of R. capsulata on cellulose was found. Cyanobacteria, viz., Anabaena, Synechococcus, and Oscillatoria sp., have been studied for photoproduction of H2. Immobilized A. cylindrica produces H2 (20 ml/g dry wt/h) continually for 1 year. Increased H2 productivity was found for Hup mutant of A. variabilis. Synechococcus sp. has a high potential for H2 production in fermentors and outdoor cultures. Simultaneous productions of oxychemicals and H2 by Klebseilla sp. and by enzymatic methods were also attempted. The fate of H2 biotechnology is presumed to be dictated by the stock of fossil fuel and state of pollution in future.
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Affiliation(s)
- R Nandi
- Department of Applied Biochemistry, Indian Institute of Chemical Biology, Calcutta, India
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Collman JP, Wagenknecht PS, Hutchison JE. Cofaciale Bis(metallo)diporphyrine als potentielle molekulare Katalysatoren für Mehrelektronenreduktionen und -oxidationen kleiner Moleküle. Angew Chem Int Ed Engl 1994. [DOI: 10.1002/ange.19941061505] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Schlereth DD, Fernández VM, Sánchez-Cruz M, Popov VO. Direct electron transfer between Alcaligenes eutrophus Z-1 hydrogenase and glassy carbon electrodes. ACTA ACUST UNITED AC 1992. [DOI: 10.1016/0302-4598(92)80035-f] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Schlereth DD, Fernández VM, Sánchez-Cruz M, Popov VO. Direct electron transfer between Alcaligenes eutrophus Z-1 hydrogenase and glassy carbon electrodes. J Electroanal Chem (Lausanne) 1992. [DOI: 10.1016/0022-0728(92)85109-g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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11
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Kaur P, Ro� K, Siddiqui RA, Schlegel HG. Nickel resistance of Alcaligenes denitrificans strain 4a-2 is chromosomally coded. Arch Microbiol 1990. [DOI: 10.1007/bf00423322] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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12
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Zaborosch C, Schneider K, Schlegel HG, Kratzin H. Comparison of the NH2-terminal amino acid sequences of the four non-identical subunits of the NAD-linked hydrogenases from Nocardia opaca 1b and Alcaligenes eutrophus H16. EUROPEAN JOURNAL OF BIOCHEMISTRY 1989; 181:175-80. [PMID: 2496982 DOI: 10.1111/j.1432-1033.1989.tb14708.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The cytoplasmic, NAD-linked hydrogenase of the Gram-positive hydrogen-oxidizing bacterium Nocardia opaca 1b was compared with the analogous enzyme isolated from the Gram-negative bacterium Alcaligenes eutrophus H16. The hydrogenase of N. opaca 1b was purified by a new procedure applying chromatography on phenyl-Sepharose and DEAE-Sephacel with two columns in series. A homogeneous enzyme preparation with a specific activity of 74 mumol H2 oxidized.min-1.mg protein-1 and a yield of 32% was isolated. The A. eutrophus enzyme was purified as previously published. Both enzymes are tetrameric proteins composed of four non-identical subunits (alpha, beta, gamma, delta). The four subunits of both of these enzymes were separated and isolated as single polypeptides by preparative polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Immunological comparison of the four subunits of the Nocardia hydrogenase with those of the Alcaligenes enzyme showed that the alpha, beta, gamma, and delta subunits of one organism were serologically related to the analogous subunits of the other organism. Among themselves, the four subunits do not have any serological relationship. The eight individual polypeptides were also compared with respect to the NH2-terminal amino acid sequences determined by automated Edman degradation and to the amino acid compositions. Strong sequence similarities exist between the analogous subunits isolated from the two bacteria. Within the established N-terminal sequences the similarities between both alpha, beta, gamma and delta subunits amount to 63%, 79%, 80% and 65%, respectively. No similarities exist between the different, non-analogous subunits alpha, beta, gamma and delta.
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Affiliation(s)
- C Zaborosch
- Institut für Mikrobiologie der Universität Göttingen, Federal Republic of Germany
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Knüttel K, Schneider K, Schlegel HG, Müller A. The membrane-bound hydrogenase from Paracoccus denitrificans. Purification and molecular characterization. EUROPEAN JOURNAL OF BIOCHEMISTRY 1989; 179:101-8. [PMID: 2537196 DOI: 10.1111/j.1432-1033.1989.tb14526.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The membrane-bound hydrogenase from Paracoccus denitrificans was purified 68-fold with a yield of 14.6%. The final preparation had a specific activity of 161.9 mumol H2 min-1 (mg protein)-1 (methylene blue reduction). Purification involved solubilization by Triton X-114, phase separation, chromatography on DEAE-Sephacel, ammonium-sulfate precipitation and chromatography on Procion-red HE-3B-Sepharose. Gel electrophoresis under denaturing conditions revealed two non-identical subunits with molecular masses of 64 kDa and 34 kDa. The molecular mass of the native enzyme was 100 kDa, as estimated by FPLC gel filtration in the presence of Chaps, a zwitterionic detergent. The isoelectric point of the Paracoccus hydrogenase was 4.3. Metal analysis of the purified enzyme indicated a content of 0.6 nickel and 7.3 iron atoms/molecule. ESR spectra of the reduced enzyme exhibited a close similarity to the membrane-bound hydrogenase from Alcaligenes eutrophus H16 with g values of 1.86, 1.92 and 1.98. The half-life for inactivation under air at 20 degrees C was 8 h. The Paracoccus hydrogenase reduced several electron acceptors, namely methylene blue, benzyl viologen, methyl viologen, menadione, cytochrome c, FMN, 2,6-dichloroindophenol, ferricyanide and phenazine methosulfate. The highest activity was measured with methylene blue (V = 161.9 U/mg; Km = 0.04 mM), whereas benzyl and methyl viologen were reduced at distinctly lower rates (16.5 U/mg and 12.1 U/mg, respectively). The native hydrogenase from P. denitrificans cross-reacted with purified antibodies raised against the membrane-bound hydrogenase from A. eutrophus H16. The corresponding subunits from both enzymes also showed immunological relationship. All reactions were of partial identity.
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Affiliation(s)
- K Knüttel
- Institut für Mikrobiologie der Universität Göttingen, Federal Republic of Germany
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Petrov RR, Utkin IB, Popov VO. Effect of redox potential on the activation of the NAD-dependent hydrogenase from Alcaligenes eutrophus Z1. Arch Biochem Biophys 1989; 268:287-97. [PMID: 2643385 DOI: 10.1016/0003-9861(89)90590-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A formal kinetic treatment of the autocatalytic activation cycle of the NAD-dependent hydrogenase from Alcaligenes eutrophus Z1 is presented. The value for the enzyme first-order activation rate constant is estimated to be (2.0 +/- 0.6) s-1 (pH 7.8, 25 degrees C). The effect of the redox potential on the activation properties of the NAD-dependent hydrogenase is studied. Hydrogenase activation is controlled by a midpoint redox potential of approximately -100 mV (pH 7.8). Once activated the enzyme is not immediately transformed back into an inactive state on rapid reoxidation and is able to preserve its catalytic properties for at least 3-4 h of intense oxigenation. Several lines of evidence show that the reductive activation of the NAD-dependent hydrogenase is accompanied by a structural reorganization of the protein. A possible origin of the -100 mV transition is discussed. A model for the activation process of the NAD-dependent hydrogenase is suggested.
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Affiliation(s)
- R R Petrov
- A.N. Bach Institute of Biochemistry, USSR Academy of Sciences, Moscow
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Podzuweit HG, Schneider K, Knüttel H. Comparison of the membrane-bound hydrogenases from Alcaligenes eutrophus H16 and Alcaligenes eutrophus type strain. BIOCHIMICA ET BIOPHYSICA ACTA 1987; 905:435-46. [PMID: 3689787 DOI: 10.1016/0005-2736(87)90473-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Whereas the membrane-bound hydrogenase from Alcaligenes eutrophus H16 is an integral membrane protein and can only be solubilized by detergent treatment, the membrane-bound hydrogenase of Alcaligenes eutrophus type strain was found to be present in a soluble form after cell disruption. For the enzyme of A. eutrophus H16 a new, highly effective purification procedure was developed including phase separation with Triton X-114 and triazine dye chromatography on Procion Blue H-ERD-Sepharose. The purification led to an homogeneous hydrogenase preparation with a specific activity of 269 U/mg protein (methylene blue reduction) and a yield of 45%. During purification and storage the enzyme was optimally stabilized by the presence of 0.2 mM MnCl2. The hydrogenase of A. eutrophus type strain was purified from the soluble extract by a similar procedure, however, with less specific activity and activity yield. Comparison of the two purified enzymes revealed no significant differences: They have the same molecular weight, both consist of two different subunits (Mr = 62,000, 31,000) and both have an isoelectric point near pH 7.0. They have the same electron acceptor specificity reacting with similar high rates and similar Km values. The acceptors reduced include viologen dyes, flavins, quinones, cytochrome c, methylene blue, 2,6-dichlorophenolindophenol, phenazine methosulfate and ferricyanide. Ubiquinones and NAD were not reduced. The two hydrogenases were shown to be immunologically identical and both have identical electrophoretic mobility. For the membrane-bound hydrogenase of A. eutrophus H16 it was demonstrated that this type of hydrogenase in its solubilized, purified state is able to catalyze also the reverse reaction, the H2 evolution from reduced methyl viologen.
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Kärst U, Suetin S, Friedrich CG. Purification and properties of a protein linked to the soluble hydrogenase of hydrogen-oxidizing bacteria. J Bacteriol 1987; 169:2079-85. [PMID: 3553156 PMCID: PMC212095 DOI: 10.1128/jb.169.5.2079-2085.1987] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
In Alcaligenes eutrophus, the formation of the hydrogenases and of five new peptides is subject to the hydrogenase control system. Of these, the B peptide was purified to homogeneity. This protein (Mr, 37,500) was composed of two identical subunits (Mr, 18,800). Antibodies against the B protein were used for its quantification by rocket immunoelectrophoresis. About 4% of the total protein consisted of the B protein; its molar ratio to the NAD-linked hydrogenase was about 4:1. The B protein appeared to be associated with the NAD-linked hydrogenase, as shown by gel filtration analysis with Sephadex G-200. The B protein was not detected in cells that had not expressed the hydrogenase proteins or that lacked the genetic information of the hydrogen-oxidizing character; it was also not detected in Tn5 insertional mutants that were unable to form soluble hydrogenase antigens. Immunochemical analysis of other species and genera than A. eutrophus revealed that only strains able to form a NAD-linked hydrogenase also formed B-protein antigens. The B protein is not required for the catalytic activity of soluble hydrogenase in vitro; its function is at present unknown.
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Tilak KVBR, Schneider K, Schlegel HG. Autotrophic growth of nitrogen-fixingAzospirillum species and partial characterization of hydrogenase from strain CC. Curr Microbiol 1986. [DOI: 10.1007/bf01577194] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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18
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Enzymes of the autotrophic pathway in mating partners and transconjugants of Nocardia opaca 1 b and Rhodococcus erythropolis. Arch Microbiol 1986. [DOI: 10.1007/bf00443659] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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19
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Rohde M, Johannssen W, Mayer F. Immunocytochemical localization of the soluble NAD-dependent hydrogenase in cells ofAlcaligenes eutrophus. FEMS Microbiol Lett 1986. [DOI: 10.1111/j.1574-6968.1986.tb01671.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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20
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Schneider K, Piechulla B. Isolation and immunological characterization of the four non-identical subunits of the soluble NAD-linked hydrogenase from Alcaligenes eutrophus H16. Biochimie 1986; 68:5-13. [PMID: 3089314 DOI: 10.1016/s0300-9084(86)81062-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The soluble NAD-linked hydrogenase of Alcaligenes eutrophus H16 is a tetramer consisting of 4 non-identical subunits with molecular weights of 63,000, 56,000, 30,000 and 26,000. Conditions have been elaborated to separate and isolate each of these subunits as a single polypeptide by a preparative scale of polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate (SDS). Against each of the 4 subunits, polyclonal antibodies were produced. From the crude sera isolated from rabbits, the antibodies (IgG fractions) were purified by Protein A-Sepharose chromatography. By the double immunodiffusion method, comparison of the 4 types of subunits revealed that they are in fact different polypeptides. Subunit 1 (Mr = 63,000) and subunit 2 (Mr = 56,000) only reacted with their own specific antibodies and showed no cross-reaction whatsoever with the antibodies raised against the other subunits. The only immunological relationship among the different subunits was observed with subunit 3 (Mr = 30,000) and subunit 4 (Mr = 26,000); the type of cross-reaction indicated that they are partially identical. A. eutrophus H16 contains, in addition to the soluble hydrogenase, a membrane-bound hydrogenase which is a dimer composed of 2 subunits with Mr of 61,000 and 30,000. Whereas the 2 native enzymes did not show any immunological cross-reaction with the respective antibodies, it was demonstrated by double immunofluorescence labeling on nitrocellulose filters that the larger subunit of the membrane-bound hydrogenase cross-reacted significantly with the antibodies raised against subunit 2 of the soluble hydrogenase.(ABSTRACT TRUNCATED AT 250 WORDS)
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Mergeay M, Nies D, Schlegel HG, Gerits J, Charles P, Van Gijsegem F. Alcaligenes eutrophus CH34 is a facultative chemolithotroph with plasmid-bound resistance to heavy metals. J Bacteriol 1985; 162:328-34. [PMID: 3884593 PMCID: PMC218993 DOI: 10.1128/jb.162.1.328-334.1985] [Citation(s) in RCA: 507] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Alcaligenes eutrophus strain CH34, which was isolated as a bacterium resistant to cobalt, zinc, and cadmium ions, shares with A. eutrophus strain H16 the ability to grow lithoautotrophically on molecular hydrogen, to form a cytoplasmic NAD-reducing and a membrane-bound hydrogenase, and most metabolic attributes; however, it does not grow on fructose. Strain CH34 contains two plasmids, pMOL28 (163 kilobases) specifying nickel, mercury, and cobalt resistance and pMOL30 (238 kilobases) specifying zinc, cadmium, mercury, and cobalt resistance. The plasmids are self-transmissible in homologous matings, but at low frequencies. The transfer frequency was strongly increased with IncP1 plasmids RP4 and pUZ8 as helper plasmids. The phenotypes of the wild type, cured strains, and transconjugants are characterized by the following MICs (Micromolar) in strains with the indicated phenotypes: Nic+, 2.5; Nic-, 0.6; Cob+A, 5.0; Cob+B, 20.0; Cob-, less than 0.07; Zin+, 12.0; Zin-, 0.6; Cad+, 2.5; and Cad-, 0.6. Plasmid-free cells of strain CH34 are still able to grow lithoautotrophically and to form both hydrogenases, indicating that the hydrogenase genes are located on the chromosome, in contrast to the Hox structural genes of strain H16, which are located on the megaplasmid pHG1 (450 kilobases).
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23
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Bonjour F, Aragno M. Bacillus tusciae, a new species of thermoacidophilic, facultatively chemolithoautotrophic hydrogen oxidizing sporeformer from a geothermal area. Arch Microbiol 1984. [DOI: 10.1007/bf00408386] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Kuhn M, Steinbüchel A, Schlegel HG. Hydrogen evolution by strictly aerobic hydrogen bacteria under anaerobic conditions. J Bacteriol 1984; 159:633-9. [PMID: 6378884 PMCID: PMC215690 DOI: 10.1128/jb.159.2.633-639.1984] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
When strains and mutants of the strictly aerobic hydrogen-oxidizing bacterium Alcaligenes eutrophus are grown heterotrophically on gluconate or fructose and are subsequently exposed to anaerobic conditions in the presence of the organic substrates, molecular hydrogen is evolved. Hydrogen evolution started immediately after the suspension was flushed with nitrogen, reached maximum rates of 70 to 100 mumol of H2 per h per g of protein, and continued with slowly decreasing rates for at least 18 h. The addition of oxygen to an H2-evolving culture, as well as the addition of nitrate to cells (which had formed the dissimilatory nitrate reductase system during the preceding growth), caused immediate cessation of hydrogen evolution. Formate is not the source of H2 evolution. The rates of H2 evolution with formate as the substrate were lower than those with gluconate. The formate hydrogenlyase system was not detectable in intact cells or crude cell extracts. Rather the cytoplasmic, NAD-reducing hydrogenase is involved by catalyzing the release of excessive reducing equivalents under anaerobic conditions in the absence of suitable electron acceptors. This conclusion is based on the following experimental results. H2 is formed only by cells which had synthesized the hydrogenases during growth. Mutants lacking the membrane-bound hydrogenase were still able to evolve H2. Mutants lacking the NAD-reducing or both hydrogenases were unable to evolve H2.
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Schneider K, Cammack R, Schlegel HG. Content and localization of FMN, Fe-S clusters and nickel in the NAD-linked hydrogenase of Nocardia opaca 1b. EUROPEAN JOURNAL OF BIOCHEMISTRY 1984; 142:75-84. [PMID: 6086343 DOI: 10.1111/j.1432-1033.1984.tb08252.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
By preparative polyacrylamide gel electrophoresis at pH 8.5, and in the absence of nickel ions, two types of subunit dimers of the NAD-linked hydrogenase from Nocardia opaca 1b were separated and isolated, and their properties were compared with each other as well as with the properties of the native enzyme. The intact hydrogenase contained 14.3 +/- 0.4 labile sulphur, 13.6 +/- 1.1 iron and 3.8 +/- 0.1 nickel atoms and approximately 1 FMN molecule per enzyme molecule. The oxidized hydrogenase showed an absorption spectrum with maxima (shoulders) at 380 nm and 420 nm and an electron spin resonance (ESR) spectrum with a signal at g = 2.01. The midpoint redox potential of the Fe-S cluster giving rise to this signal was +25 mV. In the reduced state, hydrogenase gave characteristic low-temperature (10-20 K) and high-temperature (greater than 40 K) ESR spectra which were interpreted as due to [4Fe-4S] and [2Fe-2S] clusters, respectively. The midpoint redox potentials of these clusters were determined to be -420 mV and -285 mV, respectively. The large hydrogenase dimer, consisting of subunits with relative molecular masses Mr, of 64000 and 31000, contained 9.9 +/- 0.4 S2- and 9.3 +/- 0.5 iron atoms per protein molecule. This dimer contained the FMN molecule, but no nickel. The absorption and ESR spectra of the large dimer were qualitatively similar to the spectra of the whole enzyme. This dimer did not show any hydrogenase activity, but reduced several electron acceptors with NADH as electron donor (diaphorase activity). The small hydrogenase dimer, consisting of subunits with Mr of 56000 and 27000, was demonstrated to have substantially different properties. For iron and labile sulphur average values of 3.9 and 4.3 atoms/dimer molecule have been determined, respectively. The dimer contained, in addition, about 2 atoms of nickel and was free of flavins. In the oxidized state this dimer showed an absorption spectrum with a broad band in the 400-nm region and a characteristic ESR signal at g = 2.01. The reduced form of the dimer was ESR-silent. The small dimer alone was diaphorase-inactive and did not reduce NAD with H2, but it displayed high H2-uptake activities with viologen dyes, methylene blue and FMN, and H2-evolving activity with reduced methyl viologen. Hydrogen-dependent NAD reduction was fully restored by recombining both subunit dimers, although the reconstituted enzyme differed from the original in its activity towards artificial acceptors and the ESR spectrum in the oxidized state.
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Wheelis M. Energy conservation and pyridine nucleotide reduction in chemoautotrophic bacteria: a thermodynamic analysis. Arch Microbiol 1984. [DOI: 10.1007/bf00413017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Schneider K, Schlegel HG, Jochim K. Effect of nickel on activity and subunit composition of purified hydrogenase from Nocardia opaca 1 b. EUROPEAN JOURNAL OF BIOCHEMISTRY 1984; 138:533-41. [PMID: 6319136 DOI: 10.1111/j.1432-1033.1984.tb07948.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The NAD-reducing hydrogenase of Nocardia opaca 1 b was found to be a soluble, cytoplasmic enzyme. N. opaca 1 b does not contain an additional membrane-bound hydrogenase. The soluble enzyme was purified to homogeneity with a yield of 19% and a final specific activity of 45 mumol H2 oxidized min-1 mg protein-1. NAD reduction with H2 was completely dependent on the presence of divalent metal ions (Ni2+, Co2+, Mg2+, Mn2+) or of high salt concentrations (0.5-1.5 M). The most specific effect was caused by NiCl2, whose optimal concentration turned out to be 1 mM. The stimulation of activity by salts was the greater the less chaotrophic the anion. Maximal activity was achieved in 0.5 M potassium phosphate. Hydrogenase was also activated by protons. The pH optimum in 50 mM triethanolamine/HCl buffer containing 1 mM NiCl2 was 7.8-8.0. In the absence of Ni2+, hydrogenase was only active at pH values below 7.0. The reduction of other electron acceptors was not dependent on metal ions or salts, even though an approximately 1.5-fold stimulation of the reactions by 0.1-10 microM NiCl2 was observed. With the most effective electron acceptor, benzyl viologen, a 50-fold higher specific activity was determined than with NAD. The total molecular weight of hydrogenase has been estimated to be 200 000 (gel filtration) and 178 000 (sucrose density gradient centrifugation, and sodium dodecyl sulfate electrophoresis) respectively. The enzyme is a tetramer consisting of non-identical subunits with molecular weights of 64 000, 56 000, 31 000 and 27 000. It was demonstrated by electrophoretic analyses that in the absence of NiCl2 and at alkaline pH values the native hydrogenase dissociates into two subunit dimers. The first dimer was dark yellow coloured, completely inactive and composed of subunits with molecular weights of 64 000 and 31 000. The second dimer was light yellow, inactive with NAD but still active with methyl viologen. It was composed of subunits with molecular weights of 56 000 and 27 000. Immunological comparison of the hydrogenase of N. opaca 1 b and the soluble hydrogenase of Alcaligenes eutrophus H16 revealed that these two NAD-linked hydrogenases are partially identical proteins.
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Tilak KVBR, Schneider K, Schlegel HG. Autotrophic growth of strains ofRhizobium and properties of isolated hydrogenase. Curr Microbiol 1984. [DOI: 10.1007/bf01576047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Mutaftschiev S, O'Brian M, Maier R. Hydrogen oxidation activity in membranes from Rhizobium japonicum. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1983. [DOI: 10.1016/0005-2728(83)90085-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Schink B. Isolation of a hydrogenase-cytochromebcomplex from cytoplasmic membranes ofXanthobacter autotrophicusGZ 29. FEMS Microbiol Lett 1982. [DOI: 10.1111/j.1574-6968.1982.tb08274.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Valentine RC, Rabson R, Sebek O, Helinski D. Roundtable discussion of research priorities. BASIC LIFE SCIENCES 1982; 19:445-68. [PMID: 7066013 DOI: 10.1007/978-1-4684-4142-0_33] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Physical evidence for plasmids in autotrophic, especially hydrogen-oxidizing bacteria. Arch Microbiol 1982. [DOI: 10.1007/bf00413517] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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LAMBERT GRANTR, SMITH GEOFFREYD. THE HYDROGEN METABOLISM OF CYANOBACTERIA (BLUE-GREEN ALGAE). Biol Rev Camb Philos Soc 1981. [DOI: 10.1111/j.1469-185x.1981.tb00360.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Lee CM, Schlegel HG. Physiological characterization ofPseudomonas pseudoflava GA3. Curr Microbiol 1981. [DOI: 10.1007/bf01566744] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
For a variety of reasons, including the potential industrial applications of hydrogenase, we are interested in the isolation and analysis of hydrogenase genes. In a program focusing on the hydrogen bacterium A. eutrophus H1 and E. coli, we have developed a preliminary concept of the interaction of hydrogenase in cellular metabolism, constructed mutants deficient in hydrogenase activity, and begun the isolation of hydrogenase genes utilizing the technology allowing the in vitro manipulation of DNA. We hope to pursue this project to its ultimate goal: the analysis of the molecular mechanisms involved in the control of expression of these genes and the development of the ability to manipulate the production of hydrogenase.
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The Electron Transport System and Hydrogenase of Paracoccus denitrificans. CURRENT TOPICS IN BIOENERGETICS 1981. [DOI: 10.1016/b978-0-12-152512-5.50009-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Cypionka H, Meyer O, Schlegel HG. Physiological characteristics of various species of strains of carboxydobacteria. Arch Microbiol 1980. [DOI: 10.1007/bf00427208] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Colbeau A, Kelley BC, Vignais PM. Hydrogenase activity in Rhodopseudomonas capsulata: relationship with nitrogenase activity. J Bacteriol 1980; 144:141-8. [PMID: 6998943 PMCID: PMC294606 DOI: 10.1128/jb.144.1.141-148.1980] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Hydrogenase activity was found in cells of Rhodopseudomonas capsulata strain B10 cultured under a variety of growth conditions either anaerobically in the light or aerobically in the dark. The highest activities were found routinely in cells grown in the presence of H2. The hydrogenase of R. capsulata was localized in the particulate fraction of the cells. High hydrogenase activities were usually observed in cells possessing an active nitrogenase. The hydrogen produced by the nitrogenase stimulated the activity of hydrogenase in growing cells. However, the synthesis of hydrogenase was not closely linked to the synthesis of nitrogenase. Hydrogenase was present in dark-grown cultures, whereas nitrogenase synthesis was not significant in the absence of light. Unlike nitrogenase, hydrogenase was present in cultures grown on NH4+. Conditions were established which allowed the synthesis of either nitrogenase or hydrogenase by resting cells. We concluded that hydrogenase can be synthesized independently of nitrogenase.
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Purification and properties of the membrane-bound hydrogenase ofPseudomonas pseudoflava GA3. Curr Microbiol 1980. [DOI: 10.1007/bf02601813] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Spencer RW, Daniels L, Fulton G, Orme-Johnson WH. Product isotope effects on in vivo methanogenesis by Methanobacterium thermoautotrophicum. Biochemistry 1980; 19:3678-83. [PMID: 6996709 DOI: 10.1021/bi00557a007] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The hydrogen in methane produced by cultures of Methanobacterium thermoautotrophicum originates from water. In H2O/D2O mixtures, a methane product isotope effect is observed that increases rapidly as the water deuterium enrichment approaches 100%. This effect is due to the intracellular production of protons from H2, catalyzed by hydrogenase, which occurs at 12% the rate of water diffusion through the cell membrane. We estimate that water diffusion through the thick cell membrane of M. thermoautotrophicum is retarded by a factor of 10(6) over the free diffusion rate. The intracellular production of H+ suggests that either (1) hydrogenase is not directly involved in the production of a chemiosmotic proton gradient or (2) if it is involved, the proton gradient exists between the cytosol and the interior of vesicles observed in this bacterium. The intrinsic deutrium product isotope effect in methanogenesis is 1.20 +/- 0.1, comparable to anabolic deuterium product isotope effects in other autotrophs. An algebraic model incorporating the intracellular H2 to H+ flux accurately predicts the distribution of deuterated methane species at all levels of water deuterium enrichment.
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Porte F, Vignais PM. Electron transport chain and energy transduction in Paracoccus denitrificans under autotrophic growth conditions. Arch Microbiol 1980. [DOI: 10.1007/bf00414348] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Weiss A, Schlegel H. Reduction of horse heart cytochromecby the membrane-bound hydrogenase ofAlcaligenes eutrophus. FEMS Microbiol Lett 1980. [DOI: 10.1111/j.1574-6968.1980.tb05073.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Doussière J, Porte F, Vignais PM. Orientation of hydrogenase in the plasma membrane of Paracoccus denitrificans. FEBS Lett 1980; 114:291-4. [PMID: 6993232 DOI: 10.1016/0014-5793(80)81136-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Schink B, Schlegel HG. The membrane-bound hydrogenase of Alcaligenes eutrophus: II. Localization and immunological comparison with other hydrogenase systems. Antonie Van Leeuwenhoek 1980; 46:1-14. [PMID: 6156647 DOI: 10.1007/bf00422224] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Immunological comparison of the soluble and the membrane-bound hydrogenase of Alcaligenes eutrophus revealed no common antigenic determinants shared by the native proteins, however, a small amount of cross-reacting material was detected after freezing and thawing. Immune precipitation assays supported previous observations indicating the membrane-bound hydrogenase to be localized in the outer surface of the cytoplasmic membrane. The membrane-bound hydrogenases of A. eutrophus and Pseudomonas pseudoflava showed close immunological relationship, and material cross-reacting to both antisera was found in membrane extracts of all hydrogen-oxidizing strains of Pseudomonas. Alcaligenes and Aquaspirillum. Material cross-reacting to the membrane-bound hydrogenase of Xanthobacter autotraphicus GZ 29 was found only in a few hydrogen-oxidizing bacteria. Material cross-reacting to the soluble hydrogenase of A. eutrophus was detected in strains of A. eutrophus and A. ruhlandii only. Comparison of the membrane-bound hydrogenase of A. eutrophus, P. pseudoflava and X. autotrophicus with hydrogenases of other physiological bacterial groups revealed serological relationship to the membrane-bound hydrogenases of the hydrogen bacteria and of Chromatium vinosum only. The results are discussed in terms of physiological, taxonomical, and evolutionary aspects.
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Nokhal TH, Schlegel HG. The regulation of hydrogenase formation as a differentiating character of strains of Paracoccus denitrificans. Antonie Van Leeuwenhoek 1980; 46:143-55. [PMID: 7002036 DOI: 10.1007/bf00444069] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Paracoccus denitrificans strains Stanier 381 (DSM 65), Morris (DSM 413), and Vogt 11 (DSM 415) and eleven newly isolated strains were compared with respect to the localization of hydrogenase and its regulation. In all strains hydrogenase was found to be membrane-bound and not able to reduce pyridine nucleotides. The enzyme was inducible in strain 381 and was found only in cells grown with hydrogen as the sole hydrogen donor; in cells grown under mixotrophic or heterotrophic conditions the hydrogenase activity was zero. In all other strains hydrogenase was constitutive and was present in cells grown under autotrophic, mixotrophic and heterotrophic conditions. Under the latter conditions the specific hydrogenase activity was even higher than under mixotrophic conditions.
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