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Noar JD, Bruno-Bárcena JM. Protons and pleomorphs: aerobic hydrogen production in Azotobacters. World J Microbiol Biotechnol 2016; 32:29. [DOI: 10.1007/s11274-015-1980-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Accepted: 11/05/2015] [Indexed: 11/28/2022]
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Hexter SV, Chung MW, Vincent KA, Armstrong FA. Unusual Reaction of [NiFe]-Hydrogenases with Cyanide. J Am Chem Soc 2014; 136:10470-7. [DOI: 10.1021/ja504942h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Suzannah V. Hexter
- Inorganic
Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks
Road, Oxford OX1 3QR, United Kingdom
| | - Min-Wen Chung
- Inorganic
Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks
Road, Oxford OX1 3QR, United Kingdom
| | - Kylie A. Vincent
- Inorganic
Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks
Road, Oxford OX1 3QR, United Kingdom
| | - Fraser A. Armstrong
- Inorganic
Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks
Road, Oxford OX1 3QR, United Kingdom
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Kothari A, Potrafka R, Garcia-Pichel F. Diversity in hydrogen evolution from bidirectional hydrogenases in cyanobacteria from terrestrial, freshwater and marine intertidal environments. J Biotechnol 2012; 162:105-14. [PMID: 22771887 DOI: 10.1016/j.jbiotec.2012.04.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Revised: 03/20/2012] [Accepted: 04/17/2012] [Indexed: 11/28/2022]
Abstract
We characterized a set of 36 strains of cyanobacteria isolated from terrestrial, freshwater and marine intertidal settings to probe their potential to produce hydrogen from excess reductant, in the hope of finding novel strains with improved traits for biohydrogen production. The set was diverse with respect to origin, morphology, taxonomy and phylogeny. We found that about one half of the strains could produce hydrogen from hydrogenases in standard assays, a trait that corresponded invariably with the presence of homologues of the gene hoxH, coding for subunit H in the bidirectional Ni-Fe hydrogenase. Strains from freshwater and intertidal settings had a high incidence of hydrogen producing, hoxH containing strains, but all terrestrial isolates were negative for both. While specific rates of hydrogen production varied among strains, some novel strains displayed rates several fold higher than those previously reported. We detected two different patterns in hydrogen production. Pattern 1, corresponding to that previously known in Synechocystis PCC 6803, encompassed strains whose hydrogenase system produced hydrogen only temporarily to revert to hydrogen consumption within a short time and after reaching moderate hydrogen concentrations. Cyanobacteria displaying pattern 2, in the genera Lyngbya and Microcoleus, tended to have higher rates, did not reverse the direction of the reaction and reached much higher concentrations of hydrogen at steady state, making them of interest as potential platforms for biohydrogen production.
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Affiliation(s)
- Ankita Kothari
- School of Life Sciences, Arizona State University, Tempe, AZ 85287-4501, USA
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Ciccolella CO, Raynard NA, Mei JHM, Church DC, Ludwig RA. Symbiotic legume nodules employ both rhizobial exo- and endo-hydrogenases to recycle hydrogen produced by nitrogen fixation. PLoS One 2010; 5:e12094. [PMID: 20838423 PMCID: PMC2930871 DOI: 10.1371/journal.pone.0012094] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2010] [Accepted: 07/16/2010] [Indexed: 11/19/2022] Open
Abstract
Background In symbiotic legume nodules, endosymbiotic rhizobia (bacteroids) fix atmospheric N2, an ATP-dependent catalytic process yielding stoichiometric ammonium and hydrogen gas (H2). While in most legume nodules this H2 is quantitatively evolved, which loss drains metabolic energy, certain bacteroid strains employ uptake hydrogenase activity and thus evolve little or no H2. Rather, endogenous H2 is efficiently respired at the expense of O2, driving oxidative phosphorylation, recouping ATP used for H2 production, and increasing the efficiency of symbiotic nodule N2 fixation. In many ensuing investigations since its discovery as a physiological process, bacteroid uptake hydrogenase activity has been presumed a single entity. Methodology/Principal Findings Azorhizobium caulinodans, the nodule endosymbiont of Sesbania rostrata stems and roots, possesses both orthodox respiratory (exo-)hydrogenase and novel (endo-)hydrogenase activities. These two respiratory hydrogenases are structurally quite distinct and encoded by disparate, unlinked gene-sets. As shown here, in S. rostrata symbiotic nodules, haploid A. caulinodans bacteroids carrying single knockout alleles in either exo- or-endo-hydrogenase structural genes, like the wild-type parent, evolve no detectable H2 and thus are fully competent for endogenous H2 recycling. Whereas, nodules formed with A. caulinodans exo-, endo-hydrogenase double-mutants evolve endogenous H2 quantitatively and thus suffer complete loss of H2 recycling capability. More generally, from bioinformatic analyses, diazotrophic microaerophiles, including rhizobia, which respire H2 may carry both exo- and endo-hydrogenase gene-sets. Conclusions/Significance In symbiotic S. rostrata nodules, A. caulinodans bacteroids can use either respiratory hydrogenase to recycle endogenous H2 produced by N2 fixation. Thus, H2 recycling by symbiotic legume nodules may involve multiple respiratory hydrogenases.
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Affiliation(s)
- Christopher O. Ciccolella
- Sinsheimer Laboratories, Department of Molecular, Cellular and Developmental Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Nathan A. Raynard
- Sinsheimer Laboratories, Department of Molecular, Cellular and Developmental Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - John H-M. Mei
- Sinsheimer Laboratories, Department of Molecular, Cellular and Developmental Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Derek C. Church
- Sinsheimer Laboratories, Department of Molecular, Cellular and Developmental Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - Robert A. Ludwig
- Sinsheimer Laboratories, Department of Molecular, Cellular and Developmental Biology, University of California Santa Cruz, Santa Cruz, California, United States of America
- * E-mail:
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Schubert KR, Evans HJ. Hydrogen evolution: A major factor affecting the efficiency of nitrogen fixation in nodulated symbionts. Proc Natl Acad Sci U S A 2010; 73:1207-11. [PMID: 16592307 PMCID: PMC430231 DOI: 10.1073/pnas.73.4.1207] [Citation(s) in RCA: 198] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Nitrogenase-dependent hydrogen evolution from detached legume nodules and from reaction mixtures containing cell-free nitrogenase has been well established, but the overall effect of hydrogen evolution on the efficiency of nitrogen fixation in vivo has not been critically assessed. This paper describes a survey which revealed that hydrogen evolution is a general phenomenon associated with nitrogen fixation by many nodulated nitrogen-fixing symbionts. An evaluation of the magnitude of energy loss in terms of the efficiency of electron transfer to nitrogen, via nitrogenase, in excised nodules suggested that hydrogen production may severely reduce nitrogen fixation in many legumes where photosynthate supply is a factor limiting fixation. With most symbionts, including soybeans, only 40-60% of the electron flow to nitrogenase was transferred to nitrogen. The remainder was lost through hydrogen evolution. In situ measurements of hydrogen evolution and acetylene reduction by nodulated soybeans confirmed the results obtained with excised nodules. In an atmosphere of air, a major portion of the total electron flux available for the reduction of atmospheric nitrogen by either excised nodules or intact nodulated plants was utilized in the production of hydrogen gas. Some non-leguminous symbionts, such as Alnus rubra, and a few legumes (i.e., Vigna sinensis) apparently have evolved mechanisms of minimizing net hydrogen production, thus increasing their efficiency of electron transfer to nitrogen. Our results indicate that the extent of hydrogen evolution during nitrogen reduction is a major factor affecting the efficiency of nitrogen fixation by many agronomically important legumes.
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Affiliation(s)
- K R Schubert
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oreg. 97331
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A novel endo-hydrogenase activity recycles hydrogen produced by nitrogen fixation. PLoS One 2009; 4:e4695. [PMID: 19277114 PMCID: PMC2650096 DOI: 10.1371/journal.pone.0004695] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2008] [Accepted: 01/16/2009] [Indexed: 12/17/2022] Open
Abstract
Background Nitrogen (N2) fixation also yields hydrogen (H2) at 1∶1 stoichiometric amounts. In aerobic diazotrophic (able to grow on N2 as sole N-source) bacteria, orthodox respiratory hupSL-encoded hydrogenase activity, associated with the cell membrane but facing the periplasm (exo-hydrogenase), has nevertheless been presumed responsible for recycling such endogenous hydrogen. Methods and Findings As shown here, for Azorhizobium caulinodans diazotrophic cultures open to the atmosphere, exo-hydrogenase activity is of no consequence to hydrogen recycling. In a bioinformatic analysis, a novel seven-gene A. caulinodans hyq cluster encoding an integral-membrane, group-4, Ni,Fe-hydrogenase with homology to respiratory complex I (NADH : quinone dehydrogenase) was identified. By analogy, Hyq hydrogenase is also integral to the cell membrane, but its active site faces the cytoplasm (endo-hydrogenase). An A. caulinodans in-frame hyq operon deletion mutant, constructed by “crossover PCR”, showed markedly decreased growth rates in diazotrophic cultures; normal growth was restored with added ammonium—as expected of an H2-recycling mutant phenotype. Using A. caulinodans hyq merodiploid strains expressing β-glucuronidase as promoter-reporter, the hyq operon proved strongly and specifically induced in diazotrophic culture; as well, hyq operon induction required the NIFA transcriptional activator. Therefore, the hyq operon is constituent of the nif regulon. Conclusions Representative of aerobic N2-fixing and H2-recycling α-proteobacteria, A. caulinodans possesses two respiratory Ni,Fe-hydrogenases: HupSL exo-hydrogenase activity drives exogenous H2 respiration, and Hyq endo-hydrogenase activity recycles endogenous H2, specifically that produced by N2 fixation. To benefit human civilization, H2 has generated considerable interest as potential renewable energy source as its makings are ubiquitous and its combustion yields no greenhouse gases. As such, the reversible, group-4 Ni,Fe-hydrogenases, such as the A. caulinodans Hyq endo-hydrogenase, offer promise as biocatalytic agents for H2 production and/or consumption.
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Krasna AI, Rittenberg D. THE INHIBITION OF HYDROGENASE BY NITRIC OXIDE. Proc Natl Acad Sci U S A 2006; 40:225-7. [PMID: 16589460 PMCID: PMC527979 DOI: 10.1073/pnas.40.4.225] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- A I Krasna
- DEPARTMENT OF BIOCHEMISTRY, COLLEGE OF PHYSICIANS AND SURGEONS, COLUMBIA UNIVERSITY
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Peck HD, Pietro AS, Gest H. ON THE MECHANISM OF HYDROGENASE ACTION. Proc Natl Acad Sci U S A 2006; 42:13-9. [PMID: 16589806 PMCID: PMC534223 DOI: 10.1073/pnas.42.1.13] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- H D Peck
- DEPARTMENT OF MICROBIOLOGY, SCHOOL OF MEDICINE, WESTERN RESERVE UNIVERSITY, CLEVELAND
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TEMPERLI A, WILSON PW. Oxidative phosphorylation and nitrogen fixation by cell-free extracts of the Azotobacter. ACTA ACUST UNITED AC 2000; 14:363-4. [PMID: 13609582 DOI: 10.1007/bf02159156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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10
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DWORKIN M, FOSTER JW. Experiments with some microorganisms which utilize ethane and hydrogen. J Bacteriol 2000; 75:592-603. [PMID: 13538930 PMCID: PMC290115 DOI: 10.1128/jb.75.5.592-603.1958] [Citation(s) in RCA: 385] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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SADANA JC, MOREY AV. Purification and properties of the hydrogenase of Desulfovibrio desulfuricans. ACTA ACUST UNITED AC 1998; 50:153-63. [PMID: 13745271 DOI: 10.1016/0006-3002(61)91072-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Menon AL, Mortenson LE, Robson RL. Nucleotide sequences and genetic analysis of hydrogen oxidation (hox) genes in Azotobacter vinelandii. J Bacteriol 1992; 174:4549-57. [PMID: 1624446 PMCID: PMC206250 DOI: 10.1128/jb.174.14.4549-4557.1992] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Azotobacter vinelandii contains a heterodimeric, membrane-bound [NiFe]hydrogenase capable of catalyzing the reversible oxidation of H2. The beta and alpha subunits of the enzyme are encoded by the structural genes hoxK and hoxG, respectively, which appear to form part of an operon that contains at least one further potential gene (open reading frame 3 [ORF3]). In this study, determination of the nucleotide sequence of a region of 2,344 bp downstream of ORF3 revealed four additional closely spaced or overlapping ORFs. These ORFs, ORF4 through ORF7, potentially encode polypeptides with predicted masses of 22.8, 11.4, 16.3, and 31 kDa, respectively. Mutagenesis of the chromosome of A. vinelandii in the area sequenced was carried out by introduction of antibiotic resistance gene cassettes. Disruption of hoxK and hoxG by a kanamycin resistance gene abolished whole-cell hydrogenase activity coupled to O2 and led to loss of the hydrogenase alpha subunit. Insertional mutagenesis of ORF3 through ORF7 with a promoterless lacZ-Kmr cassette established that the region is transcriptionally active and involved in H2 oxidation. We propose to call ORF3 through ORF7 hoxZ, hoxM, hoxL, hoxO, and hoxQ, respectively. The predicted hox gene products resemble those encoded by genes from hydrogenase-related operons in other bacteria, including Escherichia coli and Alcaligenes eutrophus.
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Affiliation(s)
- A L Menon
- Department of Biochemistry, University of Georgia, Athens 30602
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16
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Chen JC, Mortenson LE. Two open reading frames (ORFs) identified near the hydrogenase structural genes in Azotobacter vinelandii, the first ORF may encode for a polypeptide similar to rubredoxins. BIOCHIMICA ET BIOPHYSICA ACTA 1992; 1131:122-4. [PMID: 1581355 DOI: 10.1016/0167-4781(92)90111-c] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Sequencing of 744 base pairs (bp) of a cloned section of DNA from Azotobacter vinelandii reveals two complete, closely-spaced open reading frames (ORF1 and ORF2). Both ORFs are transcribed from the same DNA strand as that of the structural genes for hydrogenase (hoxK and hoxG, Menon, A.L. et al. (1990) Gene 96, 67-74), and are located downstream from the latter genes. The distance between the end of hoxG and the beginning of ORF1 is approx. 3.0 kilobases (kb). Most of the deduced amino acid sequence of ORF1 shares high homology with rubredoxin sequences. Some of the deduced amino acid sequence of ORF2 shares homology with that of a reported partial ORF from Rhodobacter capsulatus, ORF located within a region of DNA required for dihydrogen oxidation in that organism. Implications of these findings with respect to dihydrogen metabolism are discussed.
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Affiliation(s)
- J C Chen
- Department of Biochemistry, University of Georgia, Athens 30602
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Abstract
The effects of cyanide on membrane-associated and purified hydrogenase from Azotobacter vinelandii were characterized. Inactivation of hydrogenase by cyanide was dependent on the activity (oxidation) state of the enzyme. Active (reduced) hydrogenase showed no inactivation when treated with cyanide over several hours. Treatment of reversibly inactive (oxidized) states of both membrane-associated and purified hydrogenase, however, resulted in a time-dependent, irreversible loss of hydrogenase activity. The rate of cyanide inactivation was dependent on the cyanide concentration and was an apparent first-order process for purified enzyme (bimolecular rate constant, 23.1 M-1 min-1 for CN-). The rate of inactivation decreased with decreasing pH. [14C]cyanide remained associated with cyanide-inactivated hydrogenase after gel filtration chromatography, with a stoichiometry of 1.7 mol of cyanide bound per mol of inactive enzyme. The presence of saturating concentrations of CO had no effect on the rate or extent of cyanide inactivation of hydrogenases. The results indicate that cyanide can cause a time-dependent, irreversible inactivation of hydrogenase in the oxidized, activatable state but has no effect when hydrogenase is in the reduced, active state.
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Affiliation(s)
- L C Seefeldt
- Department of Biochemistry, University of California, Riverside 92521
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Abstract
Azotobacter vinelandii can grow mixotrophically with H2 plus mannose under N2-fixing conditions (T. Y. Wong and R. J. Maier, J. Bacteriol. 163:528-533, 1985). Mixotrophically grown cultures incubated in H2 transported mannose with a Vmax fourfold greater than that observed for cultures incubated in argon, but H2 did not change the apparent Km for mannose. Respiratory inhibitors, such as potassium cyanide, hydroxylamine, and p-chloromercuribenzoic acid, as well as the proton conductor carbonyl cyanide m-chlorophenyl-hydrazone inhibited mannose uptake. We suggest that one of the roles of H2 in mixotrophic metabolism is to supply energy that facilitates mannose transport.
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Affiliation(s)
- R J Maier
- Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218
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Dual substrate oxidations by Azotobacter vinelandii membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 1987. [DOI: 10.1016/0005-2728(87)90250-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Seefeldt LC, Arp DJ. Purification to homogeneity of Azotobacter vinelandii hydrogenase: a nickel and iron containing alpha beta dimer. Biochimie 1986; 68:25-34. [PMID: 3089312 DOI: 10.1016/s0300-9084(86)81064-1] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Azotobacter vinelandii hydrogenase has been purified to homogeneity from membranes. The enzyme was solubilized with Triton X-100 followed by ammonium sulfate-hexane extractions to remove lipids and detergent. The enzyme was then purified by carboxymethyl-Sepharose and octyl-Sepharose column chromatography. All purification steps were performed under anaerobic conditions in the presence of dithionite and dithiothreitol. The enzyme was purified 143-fold from membranes to a specific activity of 124 mumol of H2 uptake . min-1 . mg protein-1. Nondenaturing polyacrylamide gel electrophoresis of the hydrogenase revealed a single band which stained for both activity and protein. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed two bands corresponding to peptides of 67,000 and 31,000 daltons. Densitometric scans of the SDS-gel indicated a molar ratio of the two bands of 1.07 +/- 0.05. The molecular weight of the native enzyme was determined by three different methods. While gel permeation gave a molecular weight of 53,000, sucrose density gradient centrifugation and native polyacrylamide gel electrophoresis gave molecular weights of 98,600 +/- 10,000 and 98,600 +/- 2,000, respectively. We conclude that the A. vinelandii hydrogenase is an alpha beta dimer (98,000 daltons) with subunits of 67,000 and 31,000 daltons. Analyses for nickel and iron indicated 0.68 +/- 0.01 mol Ni/mol hydrogenase and 6.6 +/- 0.5 mol Fe/mol hydrogenase. The isoelectric point of the enzyme was 6.1 +/- 0.01. In addition, several catalytic properties of the enzyme have been examined. The Km for H2 was 0.86 microM, and H2 evolution was observed in the presence of reduced methyl viologen. The pH profile of enzyme activity with methylene blue as the electron acceptor has been determined, along with the Km and Vmax for various electron acceptors.
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Arp DJ, McCollum LC, Seefeldt LC. Molecular and immunological comparison of membrane-bound, H2-oxidizing hydrogenases of Bradyrhizobium japonicum, Alcaligenes eutrophus, Alcaligenes latus, and Azotobacter vinelandii. J Bacteriol 1985; 163:15-20. [PMID: 4008438 PMCID: PMC219074 DOI: 10.1128/jb.163.1.15-20.1985] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The membrane-bound hydrogenases of Bradyrhizobium japonicum, Alcaligenes eutrophus, Alcaligenes latus, and Azotobacter vinelandii were purified extensively and compared. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of each hydrogenase revealed two prominent protein bands, one near 60 kilodaltons and the other near 30 kilodaltons. The migration distances during nondenaturing polyacrylamide gel electrophoresis were similar for all except A. vinelandii hydrogenase, which migrated further than the other three. The amino acid composition of each hydrogenase was determined, revealing substantial similarity among these enzymes. This was confirmed by calculation of S delta Q values, which ranged from 8.0 to 26.7 S delta Q units. S delta Q is defined as sigma j(Xi,j-Xk,j)2, where i and k identify the proteins compared and Xj is the content (residues per 100) of a given amino acid of type j. The hydrogenases of this study were also compared with an enzyme-linked immunosorbent assay. Antibody raised against B. japonicum hydrogenase cross-reacted with all four hydrogenases, but to various degrees and in the order B. japonicum greater than A. latus greater than A. eutrophus greater than A. vinelandii. Antibody raised against A. eutrophus hydrogenase also cross-reacted with all four hydrogenases, following the pattern of cross-reaction A. eutrophus greater than A. latus = B. japonicum greater than A. vinelandii. Antibody raised against B. japonicum hydrogenase inhibited B. japonicum hydrogenase activity to a greater extent than the A. eutrophus and A. latus activities; no inhibition of A. vinelandii hydrogenase activity was detected. The results of these experiments indicated remarkable homology of the hydrogenases from these four microorganisms.
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Arp DJ. Rhizobium japonicum hydrogenase: purification to homogeneity from soybean nodules, and molecular characterization. Arch Biochem Biophys 1985; 237:504-12. [PMID: 3919648 DOI: 10.1016/0003-9861(85)90303-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Rhizobium japonicum hydrogenase was purified to homogeneity from soybean root nodules by four column chromatography steps after solubilization from membranes by treatment with a nonionic detergent. The specific activity was from 40 to 65 mumol H2 oxidized min-1 mg protein-1 and was increased 450-fold relative to that in bacteroids. The yield of activity was from 7 to 12%. The molecular weight of the native enzyme was 104,000 as determined by sucrose density gradient centrifugation. Electrophoresis in the presence of sodium dodecyl sulfate revealed two subunits with molecular weights of 64,000 and 35,000, indicating an alpha beta subunit structure. The amino acid content of the protein indicated 20 cysteine residues. Analysis of the metal content indicated 0.59 +/- 0.06 mol Ni/mol hydrogenase and 6.5 +/- 1.2 mol Fe/mol hydrogenase. Antisera prepared to the hydrogenase cross-reacted with the enzyme in bacteroid extracts at all stages of the purification but did not cross-react with extracts of Alcaligenes eutrophus grown under chemolithotrophic conditions. The similarity of rhizobial hydrogenase to the particulate hydrogenases of A. eutrophus and A. latus is discussed.
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Kow YW, Burris RH. Purification and properties of membrane-bound hydrogenase from Azotobacter vinelandii. J Bacteriol 1984; 159:564-9. [PMID: 6378882 PMCID: PMC215680 DOI: 10.1128/jb.159.2.564-569.1984] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Uptake hydrogenase (EC 1.12) from Azotobacter vinelandii has been purified 250-fold from membrane preparations. Purification involved selective solubilization of the enzyme from the membranes, followed by successive chromatography on DEAE-cellulose, Sephadex G-100, and hydroxylapatite. Freshly isolated hydrogenase showed a specific activity of 110 mumol of H2 uptake (min X mg of protein)-1. The purified hydrogenase still contained two minor contaminants that ran near the front on sodium dodecyl sulfate-polyacrylamide gels. The enzyme appears to be a monomer of molecular weight near 60,000 +/- 3,000. The pI of the protein is 5.8 +/- 0.2. With methylene blue or ferricyanide as the electron acceptor (dyes such as methyl or benzyl viologen with negative midpoint potentials did not function), the enzyme had pH optima at pH 9.0 or 6.0, respectively, It has a temperature optimum at 65 to 70 degrees C, and the measured half-life for irreversible inactivation at 22 degrees C by 20% O2 was 20 min. The enzyme oxidizes H2 in the presence of an electron acceptor and also catalyzes the evolution of H2 from reduced methyl viologen; at the optimal pH of 3.5, 3.4 mumol of H2 was evolved (min X mg of protein)-1. The uptake hydrogenase catalyzes a slow deuterium-water exchange in the absence of an electron acceptor, and the highest rate was observed at pH 6.0. The Km values varied widely for different electron acceptors, whereas the Km for H2 remained virtually constant near 1 to 2 microM, independent of the electron acceptors.
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Wong TY, Maier RJ. Hydrogen-oxidizing electron transport components in nitrogen-fixing Azotobacter vinelandii. J Bacteriol 1984; 159:348-52. [PMID: 6735984 PMCID: PMC215636 DOI: 10.1128/jb.159.1.348-352.1984] [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: 01/21/2023] Open
Abstract
Membranes from N2-fixing Azotobacter vinelandii were isolated to identify electron transport components involved in H2 oxidation. We found direct evidence for the involvement of cytochromes b, c, and d in H2 oxidation by the use of H2-reduced minus O2-oxidized absorption difference spectra. Carbon monoxide spectra showed that H2 reduced cytochrome d but not cytochrome o. Inhibition of H2 oxidation by cyanide was monophasic with a high Ki (135 microM); this was attributed to cytochrome d. Cyanide inhibition of malate oxidation showed the presence of an additional, low Ki (0.1 microM cyanide) component in the membranes; this was attributed to cytochrome o. However, H2 oxidation was not sensitive to this cyanide concentration. Chlorpromazine (at 160 microM) markedly inhibited malate oxidation, but it did not greatly inhibit H2 oxidation. Irradiation of membranes with UV light inhibited H2 oxidation. Adding A. vinelandii Q8 to the UV-damaged membranes partially restored H2 oxidation activity, whereas addition of UV-treated Q8 did not increase the activity. 2-n-Heptyl-4-hydroxyquinoline-N-oxide inhibited both H2 and malate oxidation.
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Wang ZC, Watt GD. H2-uptake activity of the MoFe protein component of Azotobacter vinelandii nitrogenase. Proc Natl Acad Sci U S A 1984; 81:376-9. [PMID: 6320185 PMCID: PMC344679 DOI: 10.1073/pnas.81.2.376] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The MoFe protein from Azotobacter vinelandii catalyzes the reduction of methylene blue and other oxidants by H2 under anaerobic conditions. H2 uptake followed manometrically or by 3H2 transfer from the gas to aqueous phase occurs concomitantly with methylene blue disappearance monitored optically or coulometrically. The stoichiometry was found to be 1:1 methylene blue/H2. MoFe protein oxidized by transfer of approximately 4 e- seems to be the redox state of the protein most active in the catalytic step, although both the S2O4(2-)-reduced and 6-e- oxidized state have been shown to react, but at a much lower rate. The presence of H2 in the atmosphere above the MoFe protein offers increased protection against O2 inactivation.
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Houchins JP, Burris RH. Light and dark reactions of the uptake hydrogenase in anabaena 7120. PLANT PHYSIOLOGY 1981; 68:712-6. [PMID: 16661985 PMCID: PMC425967 DOI: 10.1104/pp.68.3.712] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Reactions of the uptake hydrogenase from Anabaena 7120 (A.T.C.C. 27893, Nostoc muscorum) were examined in whole filaments, isolated heterocysts, and membrane particles. Whole filaments or isolated heterocysts that contained nitrogenase consumed H(2) in the presence of C(2)H(2) or N(2) in a light-dependent reaction. If nitrogenase was inactivated by O(2) shock, filaments catalyzed H(2) uptake to an unidentified endogenous acceptor in the light. Addition of NO(3) (-) or NO(2) (-) enhanced these rates. Isolated heterocysts consumed H(2) in the dark in the presence of electron acceptors with positive midpoint potentials, and these reactions were not enhanced by light. With acceptors of negative midpoint potential, significant light enhancement of H(2) uptake occurred. Maximum rates of light-dependent uptake were approximately 25% of the maximum dark rates observed. Membrane particles prepared from isolated heterocysts showed similar specificity for electron acceptors. These particles catalyzed a cyanide-sensitive oxyhydrogen reaction that was inactivated by O(2) at O(2) concentrations above 2%. Light-dependent H(2) uptake to low potential acceptors by these particles was inhibited by dibromothymoquinone but was insensitive to cyanide. In the presence of O(2), light-dependent H(2) uptake occurred simultaneously with the oxyhydrogen reaction. The pH optima for both types of H(2) uptake were near 7.0. These results further clarify the role of uptake hydrogenase in donating electrons to both the photosynthetic and respiratory electron transport chains of Anabaena.
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Affiliation(s)
- J P Houchins
- Department of Biochemistry, College of Agricultural and Life Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53706
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Houchins JP, Burris RH. Comparative characterization of two distinct hydrogenases from Anabaena sp. strain 7120. J Bacteriol 1981; 146:215-21. [PMID: 6783615 PMCID: PMC217072 DOI: 10.1128/jb.146.1.215-221.1981] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Two distinct hydrogenases, hereafter referred to as "uptake" and "reversible" hydrogenase, were extracted from Anabaena sp. strain 7120 and partially purified. The properties of the two enzymes were compared in cell-free extracts. Uptake hydrogenase was largely particulate, and although membrane bound, it could catalyze an oxyhydrogen reaction. Particulate and solubilized uptake hydrogenase could catalyze H2 uptake with a variety of artificial electron acceptors which had midpoint potentials above 0 mV. Reversible hydrogenase was soluble, could donate electrons rapidly to electron acceptors of both positive and negative midpoint potential, and could evolve H2 rapidly when provided with reduced methyl viologen. Uptake hydrogenase was irreversibly inactivated by O2, whereas reversible hydrogenase was reversibly inactivated and could be reactivated by exposure to dithionite or H2. Reversible hydrogenase was stable to heating at 70 degrees C, but uptake hydrogenase was inactivated with a half-life of 12 min at this temperature. Uptake hydrogenase was eluted from Sephadex G-200 in a single peak of molecular weight 56,000, whereas reversible hydrogenase was eluted in two peaks with molecular weights of 165,000 and 113,000. CO was competitive with H2 for each enzyme; the Ki's for CO were 0.0095 atm for reversible hydrogenase and 0.039 atm for uptake hydrogenase. The pH optima for H2 evolution and H2 uptake by reversible hydrogenase were 6 and 9, respectively. Uptake hydrogenase existed in two forms with pH optima of 6 and 8.5. Both enzymes had very low Km's for H2, and neither was inhibited by C2H2.
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Emerich DW, Ruiz-Argüeso T, Russell SA, Evans HJ. Investigation of the H(2) Oxidation System in Rhizobium japonicum 122 DES Nodule Bacteroids. PLANT PHYSIOLOGY 1980; 66:1061-6. [PMID: 16661577 PMCID: PMC440790 DOI: 10.1104/pp.66.6.1061] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The H(2)-oxidizing complex in Rhizobium japonicum 122 DES bacteroids failed to catalyze, at a measurable rate, (2)H(1)H exchange from a mixture of (2)H(2) and (1)H(2) in presence of (2)H(2)O and (1)H(2)O, providing no evidence for reversibility of the hydrogenase reaction in vivo. In the H(2) oxidation reaction, there was no significant discrimination between (2)H(2) and (1)H(2), indicating that the initial H(2)-activation step in the over-all H(2) oxidation reaction is not rate-limiting. By use of improved methods, an apparent K(m) for H(2) of 0.05 micromolar was determined. The H(2) oxidation reaction in bacteroids was strongly inhibited by cyanide (88% at 0.05 millimolar), theonyltrifluoroacetone, and other metal-complexing agents. Carbonyl cyanide m-chlorophenylhydrazone at 0.005 millimolar and 2,4-dinitrophenol at 0.5 millimolar inhibited H(2) oxidation and stimulated O(2) uptake. This and other evidence suggest the involvement of cytochromes and nonheme iron proteins in the pathway of electron transport from H(2) to O(2). Partial pressures of H(2) at 0.03 atmosphere and below had a pronounced inhibitory effect on endogenous respiration by bacteroid suspensions. The inhibition of CO(2) evolution by low partial pressures of H(2) suggests that H(2) utilization may result in conservation of oxidizable substrates and benefits the symbiosis under physiological conditions. Succinate, acetate, and formate at concentrations of 50 millimolar inhibited rates of H(2) uptake by 8, 29, and 25%, respectively. The inhibition by succinate was noncompetitive and that by acetate and formate was uncompetitive. A concentration of 11.6 millimolar CO(2) (initial concentration) in solution inhibited H(2) uptake by bacteroid suspensions by 18%. Further research is necessary to establish the significance of the inhibition of H(2) uptake by succinate, acetate, formate, and CO(2) in the metabolism of the H(2)-uptake-positive strains of Rhizobium.
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Affiliation(s)
- D W Emerich
- Laboratory for Nitrogen Fixation Research, Oregon State University, Corvallis, Oregon 97331
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Berlier YM, Lespinat PA. Mass-spectrometric kinetic studies of the nitrogenase and hydrogenase activities in in-vivo cultures of Azospirillum brasilense Sp. 7. Arch Microbiol 1980. [DOI: 10.1007/bf00403199] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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31
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Ecological rationale for H2 metabolism during aquatic blooms of the cyanobacterium Anabaena. Oecologia 1980; 47:43-45. [DOI: 10.1007/bf00541774] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/1980] [Indexed: 11/25/2022]
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Arp DJ, Burris RH. Purification and properties of the particulate hydrogenase from the bacteroids of soybean root nodules. BIOCHIMICA ET BIOPHYSICA ACTA 1979; 570:221-30. [PMID: 40601 DOI: 10.1016/0005-2744(79)90142-6] [Citation(s) in RCA: 77] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The uptake hydrogenase (hydrogen:ferricytochrome c3 oxidoreductase, EC 1.12.2.1) from the bacteroids of soybean root nodules infected with Rhizobium japonicum 110 has been purified and characterized. Bacteroids were prepared, then broken by sonication. The particulate enzyme was solubilized by treatment with Triton X-100 and further purified by polyethylene glycol fractionation, DEAE-cellulose and Sephadex G-100 chromatography. The specific activity has been increased 196-fold to 19.6 units/mg protein. The molecular weight is 63 300 as determined by gel filtration and 65 300 as determined by SDS-polyacrylamide gel electrophoresis, indicating that the enzyme is a monomer. The enzyme is O2 sensitive, with a half-life of 70 min when exposed to air. The pH optimum of the solubilized enzyme is near 5.5; the Km for H2 is 1.4 microM. Suitable electron acceptors are methylene blue, ferricyanide, 2,6-dichlorophenolindophenol, and cytochrome c. Benzyl viologen is reduced slowly; methyl viologen, NAD(P)+, FAD, FMN, and O2 are not reduced. The optimum temperature for activity is 65-70 degrees C with an activation energy of 9.2 kcal. H2 evolution by the enzyme has been demonstrated. The hydrogenase is well-suited to function in an environment where all the available H2 is generated in situ.
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Laane C, Haaker H, Veeger C. On the efficiency of oxidative phosphorylation in membrane vesicles of Azotobacter vinelandii and of Rhizobium leguminosarum bacteroids. EUROPEAN JOURNAL OF BIOCHEMISTRY 1979; 97:369-77. [PMID: 223842 DOI: 10.1111/j.1432-1033.1979.tb13123.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Lim ST, Shanmugam KT. Regulation of hydrogen utilisation in Rhizobium japonicum by cyclic AMP. Biochim Biophys Acta Gen Subj 1979; 584:479-92. [PMID: 222344 DOI: 10.1016/0304-4165(79)90121-1] [Citation(s) in RCA: 79] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Utilisation (uptake) of hydrogen gas by whole cells of Rhizobium japonicum was found to be influenced by the carbon source(s) present in the growth medium, with activity being highest in a medium containing sugars. Tricarboxylic acid cycle intermediates, such as malate, significantly reduced H2 utilisation. No reduction in the hydrogenase activity is observed when the enzyme is assayed directly by the tritium exchange method, indicating that the decrease in hydrogen uptake activity is not due to repression of hydrogenase biosynthesis. Cyclic AMP was found to alleviate the inhibition of H2 uptake by malate, and this requires new protein synthesis. Addition of chloramphenicol or rifampicin simultaneously with cyclic AMP eliminated the stimulation of H2 uptake in the malate medium. These results show that in R. japonicum cyclic AMP plays a major role in the regulation of H2 metabolism.
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Ruiz-Arg�eso T, Emerich DW, Evans HJ. Characteristics of the H2 oxidizing system in soybean nodule bacteroids. Arch Microbiol 1979. [DOI: 10.1007/bf00425056] [Citation(s) in RCA: 17] [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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Emerich DW, Ruiz-Argüeso T, Ching TM, Evans HJ. Hydrogen-dependent nitrogenase activity and ATP formation in Rhizobium japonicum bacteroids. J Bacteriol 1979; 137:153-60. [PMID: 762010 PMCID: PMC218429 DOI: 10.1128/jb.137.1.153-160.1979] [Citation(s) in RCA: 151] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Rhizobium japonicum 122 DES bacteroids from soybean nodules possess an active H(2)-oxidizing system that recycles all of the H(2) lost through nitrogenase-dependent H(2) evolution. The addition of 72 muM H(2) to suspensions of bacteroids increased O(2) uptake 300% and the rate of C(2)H(2) reduction 300 to 500%. The optimal partial pressure of O(2) was increased, and the partial pressure of O(2) range for C(2)H(2) reduction was extended by adding H(2). A supply of succinate to bacteroids resulted in effects similar to those obtained by adding H(2). Both H(2) and succinate provided respiratory protection for the N(2)-fixing system in bacteroids. The oxidation of H(2) by bacteroids increased the steady-state pool of ATP by 20 to 40%. In the presence of 50 mM iodoacetate, which caused much greater inhibition of endogenous respiration than of H(2) oxidation, the addition of H(2) increased the steady-state pool of ATP in bacteroids by 500%. Inhibitor evidence and an absolute requirement for O(2) indicated that the H(2)-stimulated ATP synthesis occurred through oxidative phosphorylation. In the presence of 50 mM iodoacetate, H(2)-dependent ATP synthesis occurred at a rate sufficient to support nitrogenase activity. The addition of H(2) to H(2) uptake-negative strains of R. japonicum had no effect on ATP formation or C(2)H(2) reduction. It is concluded that the H(2)-oxidizing system in H(2) uptake-positive bacteroids benefits the N(2)-fixing process by providing respiratory protection of the O(2)-labile nitrogenase proteins and generating ATP to support maximal rates of C(2)H(2) reduction by oxidation of the H(2) produced from the nitrogenase system.
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Hallenbeck P, Benemann J. Characterization and partial purification of the reversible hydrogenase of Anabaena cylindrica. FEBS Lett 1978. [DOI: 10.1016/0014-5793(78)80951-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Abstract
A survey on organisms able to use molecular hydrogen as electron donor in the energy-yielding process is presented. In the group of the aerobic hydrogen-oxidizing bacteria so far two types of hydrogenases have been encountered, a NAD-reducing, soluble enzyme (H2 : NAD oxidoreductase) and a membrane-bound enzyme unable to reduce pyridine nucleotides. With respect to the distribution of both types of hydrogenases three groups of hydrogen-oxidizing bacteria can be diffentiated containing (i) both types (Alcaligenes eutrophus), (ii) a soluble enzyme only (Nocardia opaca lb), and (iii) a membrane-bound hydrogenase only (majority of genera and species). The results of studies on the NAD-specific hydrogenase of A. eutrophus are summarized. Results on the solubilization and purification of the membrane-bound hydrogenase of A. eutrophus are presented in detail. The enzyme was solubilized from purified membranes by Triton X-100 and sodium desoxycholate or phospholipase D. The crude membrane extract was fractionated by ammonium sulfate precipitation and chromatography on carboxymethylcellulose at pH 5.5. The enzyme was stable in potassium phosphate buffer; it resembles the soluble enzyme with respect to stability under oxidizing conditions. Further biochemical and immunological data indicate, however, that both enzymes are different with respect to their native structure.
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Abstract
This manuscript reviews the literature on hydrogen metabolism in blue-green algae and reports some new data from this laboratory. H2-formation by intact cells is found to be catalyzed exclusively by nitrogenase. Its rate appears to be variable from strain to strain used byt is--in our hands--very small. Therefore, blue-green algae are presumably of limited value in projects of solar energy conversion to form molecular hydrogen. These organisms are also able to consume the gas in a reaction catalysed by hydrogenase. Hydrogen is mainly consumed in an oxygen dependent reaction, as in aerobic nitrogen fixing bacteria. It can also serve as an electron donor for nitrogen fixation under certain physiological conditions. In experiments with a cell-free preparation, hydrogenase is found to be membrane-bound. The enzyme is characterized with respect to its specifity towards electron donors and acceptors.
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Abstract
H2 will support nitrogenase activity (C2H2 reduction) in Azotobacter chroococcum with or without added carbon substrate. Results show that H2 is metabolised to transfer electrons to nitrogenase and to the respiratory chain to produce ATP. H2-supported nitrogenase activity is most significant at low carbon substrate concentrations, but also occurs at saturating concentration. Continuous cultures of N2-fixing A. chroococcum evolved H2 from nitrogenase under O2-N2- and C-limited conditions. This H2 represented a significant proportion of nitrogenase activity. Hydrogenase activity was consistently high under C-limited conditions, but low or undetectable under O2- and N2-limitations. Pre-treatment with 40 per cent C2H2 inhibited hydrogenase activity in C-limited cultures, and H2 evolution increased under air and under Ar:O2 (4:1) mixtures. We deduce that hydrogenase : I, recycles H2 produced by nitrogenase to provide electrons and energy for N2 reduction: II, supports respiratory protection for nitrogenase under C-limited conditions, and III, does not act to prevent any inhibition of N2 reduction by H2 produced by nitrogenase. A scheme for the H2 cycle in N2-fixing A. chroococcum is proposed.
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Lespinat PA, Gester R, Berlier Y. Direct mass-spectrometric determination of the relationship between respiration, hydrogenase and nitrogenase activities in Azotobacter chroococcum. Biochimie 1978; 60:339-41. [PMID: 667186 DOI: 10.1016/s0300-9084(78)80831-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Schubert KR, Jennings NT, Evans HJ. Hydrogen Reactions of Nodulated Leguminous Plants: II. Effects on Dry Matter Accumulation and Nitrogen Fixation. PLANT PHYSIOLOGY 1978; 61:398-401. [PMID: 16660301 PMCID: PMC1091876 DOI: 10.1104/pp.61.3.398] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The interaction between the ATP-dependent evolution of H(2) catalyzed by nitrogenase and the oxidation of H(2) via a hydrogenase has been postulated to influence the efficiency of the N(2)-fixing process in nodulated legumes. A comparative study using soybean (Glycine max L. Merr.) cv. Anoka inoculated with either Rhizobium japonicum strain USDA 31 or USDA 110 and cowpea (Vigna unguiculata L. Walp.) cv. Whippoorwill inoculated with Rhizobium strain 176A27 or 176A28 cultured on a N-free medium was conducted to address this question. Nodules from the Anoka cultivar inoculated with USDA 31 evolved H(2) in air and the H(2) produced accounted for about 30% of the energy transferred to the nitrogenase system during the period of active N(2) fixation. In contrast the same soybean cultivar inoculated with USDA 110 produced nodules with an active hydrogenase and consequently did not evolve H(2) in air. A comparison of Anoka soybeans inoculated with the two different strains of R. japonicum showed that mean rates of C(2)H(2) reduction and O(2) consumption and mean mass of nodules taken at four times during vegetative growth were not significantly different.When compared to Anoka inoculated with USDA 31, the same cultivar inoculated with USDA 110 showed increases in total dry matter, per cent nitrogen, and total N(2) fixed of 24, 7, and 31%, respectively. Cowpeas in symbiosis with the hydrogenase-producing strain 176A28 in comparison with the same cultivar inoculated with the H(2)-evolving strain 176A27 produced increases in plant dry weight and total N(2) fixed of 11 and 15%, respectively. This apparent increase in the efficiency of N(2) fixation for nodulated legumes capable of reutilizing the H(2) evolved from nitrogenase is considered and it is concluded that provision of conclusive evidence of the role of the H(2)-recycling process in N(2)-fixing efficiency of legumes will require comparison of Rhizobium strains that are genetically identical with the exception of the presence of hydrogenase.
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Affiliation(s)
- K R Schubert
- Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331
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Peterson RB, Burris RH. Hydrogen metabolism in isolated heterocysts of Anabaena 7120. Arch Microbiol 1978. [DOI: 10.1007/bf00406027] [Citation(s) in RCA: 83] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Stouthamer AH. Theoretical calculations on the influence of the inorganic nitrogen source on parameters for aerobic growth of microorganisms. Antonie Van Leeuwenhoek 1977; 43:351-67. [PMID: 603236 DOI: 10.1007/bf02313762] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Bothe H, Tennigkeit J, Eisbrenner G. The utilization of molecular hydrogen by the blue-green alga Anabaena cylindrica. Arch Microbiol 1977; 114:43-9. [PMID: 410380 DOI: 10.1007/bf00429628] [Citation(s) in RCA: 96] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Andersen K, Shanmugam KT, Valentine RC. Nitrogen fixation (NIF) regulatory mutants of Klebsiella: determination of the energy cost of N2 fixation in vivo. BASIC LIFE SCIENCES 1977; 9:95-110. [PMID: 336030 DOI: 10.1007/978-1-4684-0880-5_9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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49
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Bothe H, Tennigkeit J, Eisbrenner G, Yates MG. The hydrogenase-nitrogenase relationship in the blue-green algaAnabaena cylindrica. PLANTA 1977; 133:237-242. [PMID: 24425256 DOI: 10.1007/bf00380683] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/1976] [Accepted: 09/23/1976] [Indexed: 06/03/2023]
Abstract
Nitrogen-fixingAnabaena cylindrica cells are found to evolve hydrogen in high quantities in the presence of CO plus C2H2. Studies with the inhibitors dichlorophenyldimethylurea (DCMU), disalicylidenepropanediamine (DSPD), dibromothymoquinone (DBMIB), undecylbenzimidazole (UDB) and chloro-carbonyl-cyanide-phenylhydrazone (CCCP) and also withAnabaena grown on nitrate- and ammonia-nitrogen show that the H2-formation is due to the ATP-dependent H3O(+)-reduction catalysed by nitrogenase. In control experiments CO plus C2H2 inhibited the activities of a cell-free hydrogenase fromClostridium pasteurianum. It is concluded that Anabaena has a hydrogenase whose natural function is to recycle the H2 lost by the action of nitrogenase.
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Affiliation(s)
- H Bothe
- Botanisches Institut der Universität Heidelberg, Hofmeisterweg 4, D-6900, Heidelberg, Germany
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50
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Smith LA, Hill S, Yates MG. Inhibition by acetylene of conventional hydrogenase in nitrogen-fixing bacteria. Nature 1976; 262:209-10. [PMID: 778640 DOI: 10.1038/262209a0] [Citation(s) in RCA: 107] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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