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Kim JYH, Cha HJ. Recent progress in hydrogenase and its biotechnological application for viable hydrogen technology. KOREAN J CHEM ENG 2013. [DOI: 10.1007/s11814-012-0208-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Lambert GR, Cantrell MA, Hanus FJ, Russell SA, Haddad KR, Evans HJ. Intra- and interspecies transfer and expression of Rhizobium japonicum hydrogen uptake genes and autotrophic growth capability. Proc Natl Acad Sci U S A 2010; 82:3232-6. [PMID: 16578786 PMCID: PMC397749 DOI: 10.1073/pnas.82.10.3232] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cosmids containing hydrogen uptake genes have previously been isolated in this laboratory. Four new cosmids that contain additional hup gene(s) have now been identified by conjugal transfer of a Rhizobium japonicum 122DES gene bank into a Tn5-generated Hup(-) mutant and screening for the acquisition of Hup activity. The newly isolated cosmids, pHU50-pHU53, contain part of the previously isolated pHU1 but extend as far as 20 kilobases beyond its border. pHU52 complements five of six Hup(-) mutants and confers activity on several Hup(-) wild-type R. japonicum strains in the free-living state and where tested in nodules. Transconjugants obtained from interspecies transfer of pHU52 to Rhizobium meliloti 102F28, 102F32, and 102F51 and Rhizobium leguminosarum 128C53 showed hydrogen-dependent methyleneblue reduction, performed the oxyhydrogen reaction, and showed hydrogen-dependent autotrophic growth by virtue of the introduced genes. The identity of the presumptive transconjugants was confirmed by antibiotic-resistance profiles and by plant nodulation tests.
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Affiliation(s)
- G R Lambert
- Laboratory for Nitrogen Fixation Research, Oregon State University, Corvallis, OR 97331
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Lambert GR, Harker AR, Cantrell MA, Hanus FJ, Russell SA, Haugland RA, Evans HJ. Symbiotic Expression of Cosmid-Borne Bradyrhizobium japonicum Hydrogenase Genes. Appl Environ Microbiol 2010; 53:422-8. [PMID: 16347291 PMCID: PMC203676 DOI: 10.1128/aem.53.2.422-428.1987] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The expression of cosmid-borne Bradyrhizobium japonicum hydrogenase genes in alfalfa, clover, and soybean nodules harboring Rhizobium transconjugants was studied. Cosmid pHU52 conferred hydrogen uptake (Hup) activity in both free-living bacteria and in nodules on the different plant hosts, although in nodules the instability of the cosmid resulted in low levels of Hup activity. In contrast, cosmid pHU1, which does not confer Hup activity on free-living bacteria, gave a Hup phenotype in nodules on alfalfa and soybean. Nodules formed by B. japonicum USDA 123Spc(pHU1) recycled about 90% of nitrogenase-mediated hydrogen evolution. Both subunits of hydrogenase (30- and 60-kilodalton polypeptides) were detected in enzyme-linked immunosorbent assays of bacteroid preparations from nodules harboring B. japonicum strains with pHU1 or pHU52. Neither pHU53 nor pLAFR1 conferred detectable Hup activity in either nodules or free-living bacteria. Based on the physical maps of pHU1 and pHU52, it is suggested that a 5.5-kilobase EcoRI fragment unique to pHU52 contains a gene or part of a gene required for Hup activity in free-living bacteria but not in nodules. This conclusion is supported by the observation that two Tn5 insertions in the chromosome of B. japonicum USDA 122DES obtained by marker exchange with Tn5-mutagenized pHU1 abolished Hup activity in free-living bacteria but not in nodules.
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Affiliation(s)
- G R Lambert
- Laboratory for Nitrogen Fixation Research, Oregon State University, Corvallis, Oregon 97331
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Kalia VC, Lal S, Ghai R, Mandal M, Chauhan A. Mining genomic databases to identify novel hydrogen producers. Trends Biotechnol 2003; 21:152-6. [PMID: 12679062 DOI: 10.1016/s0167-7799(03)00028-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The realization that fossil fuel reserves are limited and their adverse effect on the environment has forced us to look into alternative sources of energy. Hydrogen is a strong contender as a future fuel. Biological hydrogen production ranges from 0.37 to 3.3 moles H(2) per mole of glucose and, considering the high theoretical values of production (4.0 moles H(2) per mole of glucose), it is worth exploring approaches to increase hydrogen yields. Screening the untapped microbial population is a promising possibility. Sequence analysis and pathway alignment of hydrogen metabolism in complete and incomplete genomes has led to the identification of potential hydrogen producers.
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Affiliation(s)
- Vipin C Kalia
- Institute of Genomics and Integrative Biology/CSIR, Delhi University Campus, Mall Delhi Road, 11 00 07, India.
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Holland MA, Polacco JC. Urease-null and hydrogenase-null phenotypes of a phylloplane bacterium reveal altered nickel metabolism in two soybean mutants. PLANT PHYSIOLOGY 1992; 98:942-8. [PMID: 16668768 PMCID: PMC1080291 DOI: 10.1104/pp.98.3.942] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Mutation at either of two genetic loci (Eu2 or Eu3) in soybean (Glycine max [L.] Merr.) results in a pleiotropic elimination of the activity of both major urease isozymes. Surprisingly, the phenotype of a phylloplane bacterium, Methylobacterium mesophilicum, living on the leaves of eu2/eu2 or eu3-e1/eu3-e1 mutants is also affected by these plant mutations. The bacteria isolated from leaves of these soybean mutants have transient urease- and hydrogenase-deficient phenotypes that can be corrected by the addition of nickel to free-living cultures. The same bacterium growing on wild-type soybeans or on urease mutants eu1-sun/eu1-sun or eu4/eu4, each deficient in only one urease isozyme, are urease-positive. These results suggest that the bacterium living on the eu2/eu2 or eu3-e1/eu3-e1 mutant is unable to produce an active urease or hydrogenase because it is effectively starved for nickel. We infer that mutations at Eu2 or Eu3 result in defects in nickel metabolism but not in Ni(2+) uptake or transport, because eu2/eu2 and eu3-e1/eu3-e1 mutants exhibit normal uptake of (63)NiCl(2). Moreover, wild-type plants grafted on mutant rootstocks produce seeds with fully active urease, indicating unimpeded transport of nickel through mutant roots and stems.
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Affiliation(s)
- M A Holland
- Department of Biochemistry, 111 Schweitzer Hall, University of Missouri, Columbia, Missouri 65211
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Toussaint B, Bosc C, Richaud P, Colbeau A, Vignais PM. A mutation in a Rhodobacter capsulatus gene encoding an integration host factor-like protein impairs in vivo hydrogenase expression. Proc Natl Acad Sci U S A 1991; 88:10749-53. [PMID: 1961742 PMCID: PMC53008 DOI: 10.1073/pnas.88.23.10749] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
A gene capable of encoding a protein sharing 45% identical amino acids with the alpha subunit of the integration host factor (IHF) of Escherichia coli was isolated from the photosynthetic bacterium Rhodobacter capsulatus strain B10 by complementation of a hydrogenase-deficient (Hup-) mutant, IR4. A DNA fragment of 274 base pairs containing an IHF binding consensus sequence, isolated from the promoter region of the hydrogenase structural genes (hupSL), was shown by gel retardation assays to bind the IHF protein from E. coli. The product of the R. capsulatus gene was shown to bind specifically to the 274-base-pair DNA fragment from the hupSL promoter. By analogy to the E. coli himA gene, which encodes the alpha subunit of IHF, the gene complementing the IR4 mutant was named himA of R. capsulatus. The wild-type himA gene, cloned in plasmid pBO2, was introduced into the IR4 strain and shown to restore, in trans, hydrogenase activity and autotrophic growth in the mutant. In IR4, a C----T transition mutation had replaced Arg-8 by Cys-8. Gel mobility shifts of the 274-base-pair DNA fragment, not observed with the himA gene product of IR4, were restored with extracts from IR4(pBO2) cells, containing the himA gene on the recombinant plasmid pBO2.
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Affiliation(s)
- B Toussaint
- Laboratoire de Biochimie Microbienne (Unité de Recherche Associée 1130 du Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale), Grenoble, France
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Delgado M, Drevon J, Bedmar E. Denitrification by bacteroids of an uptake hydrogenase negative (Hup â) mutant and its isogenic Hup +parental strain of Bradyrhizobium japonicum. FEMS Microbiol Lett 1991. [DOI: 10.1111/j.1574-6968.1991.tb04340.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Unusual genetic phenomena associated with Tn5 mutagenesis in Alcaligenes eutrophus strain H1. Arch Microbiol 1989. [DOI: 10.1007/bf00409665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Xu HW, Love J, Borghese R, Wall JD. Identification and isolation of genes essential for H2 oxidation in Rhodobacter capsulatus. J Bacteriol 1989; 171:714-21. [PMID: 2536678 PMCID: PMC209656 DOI: 10.1128/jb.171.2.714-721.1989] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Mutants of Rhodobacter capsulatus unable to grow photoautotrophically with H2 and CO2 were isolated. Those lacking uptake hydrogenase activity as measured by H2-dependent methylene blue reduction were analyzed genetically and used in complementation studies for the isolation of the wild-type genes. Results of further subcloning and transposon Tn5 mutagenesis suggest the involvement of a minimum of five genes. Hybridization to the 2.2-kilobase-pair SstI fragment that lies within the coding region for the large and small subunits of Bradyrhizobium japonicum uptake hydrogenase showed one region of strong homology among the R. capsulatus fragments isolated, which we interpret to mean that one or both structural genes were among the genes isolated.
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Affiliation(s)
- H W Xu
- Biochemistry Department, University of Missouri-Columbia 65211
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Cloning of a DNA region from Bradyrhizobium japonicum encoding pleiotropic functions in heme metabolism and respiration. Arch Microbiol 1989. [DOI: 10.1007/bf00413131] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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O'Brian MR, Maier RJ. Hydrogen metabolism in Rhizobium: energetics, regulation, enzymology and genetics. Adv Microb Physiol 1988; 29:1-52. [PMID: 3132815 DOI: 10.1016/s0065-2911(08)60345-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- M R O'Brian
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218
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Harker AR, Zuber M, Evans HJ. Immunological homology between the membrane-bound uptake hydrogenases of Rhizobium japonicum and Escherichia coli. J Bacteriol 1986; 165:579-84. [PMID: 3511036 PMCID: PMC214458 DOI: 10.1128/jb.165.2.579-584.1986] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Two polypeptides present in aerobic and anaerobic cultures of Escherichia coli HB101 were shown to cross-react with antibodies to the 30- and 60-kilodalton (kDa) subunits of the uptake hydrogenase of Rhizobium japonicum. The cross-reactive polypeptides in a series of different E. coli strains are of Mrs ca. 60,000 and 30,000, and both polypeptides are present in proportion to measurable hydrogen uptake (Hup) activity (r = 0.95). The 60-kDa polypeptide from E. coli HB101 comigrated on native gels with detectable Hup activity. The exact role of the 30-kDa polypeptide in E. coli is unclear. E. coli MBM7061, a natural Hup- variant, grown anaerobically or aerobically lacked detectable Hup activity and failed to cross-react with the antisera against the hydrogenase from R. japonicum. Anaerobically cultured E. coli MBM7061, however, did express formate hydrogenlyase activity, indicating that the hydrogenases involved in the oxygen-dependent activation of hydrogen and the formate-dependent evolution of hydrogen are biochemically distinct.
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Colbeau A, Godfroy A, Vignais PM. Cloning of DNA fragments carrying hydrogenase genes of Rhodopseudomonas capsulata. Biochimie 1986; 68:147-55. [PMID: 3015242 DOI: 10.1016/s0300-9084(86)81079-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A cosmid library of Rhodopseudomonas capsulata DNA was constructed in Escherichia coli HB101 using the broad-host-range cosmid vector pLAFR1. More than ninety per cent of the clones in the bank contained cosmids with DNA inserts averaging 20 kilobase pairs in length. Mutants deficient in uptake hydrogenase (Hup-) were obtained from R. capsulata strain B10 by ethylmethylsulfonate (EMS) mutagenesis. The content of hydrogenase protein in Hup- mutant cells was tested by rocket immunoelectrophoresis. Hup- mutants (Rifr) were complemented with the clone bank by conjugation and, from the transconjugants selected by rifampicin and tetracycline resistance, Hup+ transconjugants were screened for the ability to grow photoautotrophically and to reduce methylene blue in a colony assay. The recombinant plasmid pAC57 restored hydrogenase activity in the Hup- mutants RCC8, RCC10, RCC12 and ST410 whereas pAG202 restored that of IR4. The cloned R. capsulata DNA insert of pAC57 gave 5 restriction fragments by cleavage with EcoRI endonuclease. Fragment 1 (7 kb) restored hydrogenase activity in Hup- mutant strains RCC12 and ST410 and fragment 5 (1.3 kb) in strains RCC8 and RCC10. Since the 2 cosmids pAC57 and pAG202 are different cosmids, as indicated by restriction analyses and absence of cross hybridization, it is concluded that at least two hup genes are required for the expression of hydrogenase activity in R. capsulata.
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Harker AR, Lambert GR, Hanus FJ, Evans HJ. Further evidence that two unique subunits are essential for expression of hydrogenase activity in Rhizobium japonicum. J Bacteriol 1985; 164:187-91. [PMID: 3900036 PMCID: PMC214228 DOI: 10.1128/jb.164.1.187-191.1985] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Eight strains of Rhizobium lacking hydrogenase uptake (Hup) activity and 17 transconjugant strains carrying the hup cosmids pHU1, pHU52, or pHU53 (G. R. Lambert, M. A. Cantrell, F. J. Hanus, S. A. Russell, K. R. Haddad, and H. J. Evans, Proc. Natl. Acad. Sci. USA, 82:3232-3236, 1985) were screened for Hup activity and the presence of immunologically detectable hydrogenase polypeptides. Crude extracts of these strains were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot analysis with affinity-purified antibodies against the two subunits of purified hydrogenase (Mr 60,000 and 30,000). Derepressed transconjugants carrying the cosmid pHU52 were Hup+ and contained detectable levels of both hydrogenase subunit polypeptides. Non-derepressed strains, Hup- parent strains, and strains carrying cosmids other than pHU52 did not express Hup activity and contained no immunologically detectable protein. These data provide further evidence for the essential involvement of the smaller (Mr 30,000) subunit in the expression of hydrogenase activity in Rhizobium japonicum and suggest that the determinants for hydrogenase subunit synthesis are present on pHU52.
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Lambert GR, Hanus FJ, Russell SA, Evans HJ. Determination of the Hydrogenase Status of Individual Legume Nodules by a Methylene Blue Reduction Assay. Appl Environ Microbiol 1985; 50:537-9. [PMID: 16346869 PMCID: PMC238657 DOI: 10.1128/aem.50.2.537-539.1985] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We adapted a method for the rapid screening of colonies of free-living
Rhizobium japonicum
for hydrogenase activity to determine the hydrogenase status of individual soybean nodules. Crude bacteroid suspensions from nodules containing strains known to be hydrogen uptake positive (Hup
+
) caused a localized decolorization of filter paper disks, whereas suspensions from nodules arising from inoculation with hydrogen uptake-negative (Hup
−
) mutants or strains did not decolorize the disks. The reliability of the method was demonstrated by its successful application to 29 slow-growing rhizobia. The Hup phenotype on methylene blue filters agreed with that determined amperometrically with either methylene blue or oxygen as the electron acceptor.
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Affiliation(s)
- G R Lambert
- Laboratory for Nitrogen Fixation Research, Oregon State University, Corvallis, Oregon 97331
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Voordouw G, Walker JE, Brenner S. Cloning of the gene encoding the hydrogenase from Desulfovibrio vulgaris (Hildenborough) and determination of the NH2-terminal sequence. EUROPEAN JOURNAL OF BIOCHEMISTRY 1985; 148:509-14. [PMID: 3888620 DOI: 10.1111/j.1432-1033.1985.tb08868.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: 01/07/2023]
Abstract
The gene encoding the hydrogenase from Desulfovibrio vulgaris (Hildenborough) has been cloned in Escherichia coli. D. vulgaris DNA was digested with the restriction endonucleases EcoRI and SalI and ligated into the vector pUC9 [Vieira, J. & Messing, J. (1982) Gene 19, 259-268], which had been cut with these same enzymes. Approximately 9000 recombinant clones were obtained by transformation of E. coli JM 101 followed by growth on rich plates with ampicillin for selection and isopropyl-beta-D-thiogalactoside and 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside present for detection of recombinants. The recombinant clones were then screened for production of immunoreactive proteins with rabbit antisera against purified hydrogenase and 125I-labelled protein A. 28 positive clones were found in this initial screening. These were further tested in an immunocompetition experiment, which showed that the protein product from one clone behaved identically to purified hydrogenase. The plasmid pHV15 isolated from this clone has a 4.7 X 10(3)-base-pair SalI/EcoRI insert. Cells of E. coli JM 101 transformed with pHV 15 produce a hydrogenase polypeptide of molecular mass 46 kDa as detected by Western blotting. The mass, as well as the Cleveland mapping pattern of the polypeptide produced by E. coli, are identical with those of the hydrogenase isolated from D. vulgaris (Hildenborough). Southern blotting of restriction-enzyme-digested D. vulgaris DNA, using the nick-translated 4.7 X 10(3)-base-pair SalI/EcoRI fragment as a probe, indicates the presence of a single gene with an internal PstI site. The NH2-terminal sequence of the hydrogenase was determined to be: (sequence in text). This information should allow an unambiguous identification of the hydrogenase gene.
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Schlegel HG, Meyer M. Isolation of hydrogenase regulatory mutants of hydrogen-oxidizing bacteria by a colony-screening method. Arch Microbiol 1985. [DOI: 10.1007/bf00428853] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Tichy H, Lotz W. Screening method for the detection of uptake hydrogenase activity of Rhizobium leguminosarumbacteroids. FEMS Microbiol Lett 1985. [DOI: 10.1111/j.1574-6968.1985.tb01648.x] [Citation(s) in RCA: 4] [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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Vignais PM, Colbeau A, Willison JC, Jouanneau Y. Hydrogenase, nitrogenase, and hydrogen metabolism in the photosynthetic bacteria. Adv Microb Physiol 1985; 26:155-234. [PMID: 3913292 DOI: 10.1016/s0065-2911(08)60397-5] [Citation(s) in RCA: 119] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Haugland RA, Cantrell MA, Beaty JS, Hanus FJ, Russell SA, Evans HJ. Characterization of Rhizobium japonicum hydrogen uptake genes. J Bacteriol 1984; 159:1006-12. [PMID: 6090382 PMCID: PMC215760 DOI: 10.1128/jb.159.3.1006-1012.1984] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Recombinant cosmids from a gene library of the DNA from Hup+ Rhizobium japonicum 122DES previously have been shown to restore hydrogenase activity when transferred by conjugation into certain Hup- mutants of R. japonicum. We generated a restriction map covering 32.2 kilobases of this cosmid DNA. At least 25.3 kilobases of the cosmid pHU1 were shown to have the same arrangement as those in the genome of strain 122DES. Analysis of Tn5 insertions into the 122DES genome indicates that hup-specific sequences occur in a region spanning about 15 kilobases of insert DNA within pHU1. Introduction of pHU1 into five out of six R. japonicum Hup- mutants resulted in a Hup+ phenotype in some transconjugants. Three of the mutations appear to be in transcriptional units completely contained within pHU1, whereas the other two must be in genes that are at least partially contained within pHU1. pBR235 derivatives containing fragments of hup DNA can be transferred into the R. japonicum Hup- mutant PJ18nal if the derivatives contain a region of homology with the R. japonicum genome. The hup mutation in strain PJ18nal appears to be dominant. The hup genes in R. japonicum strain 122DES appear to be organized in at least two, and probably three, transcriptional units.
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Harker AR, Xu LS, Hanus FJ, Evans HJ. Some properties of the nickel-containing hydrogenase of chemolithotrophically grown Rhizobium japonicum. J Bacteriol 1984; 159:850-6. [PMID: 6384183 PMCID: PMC215736 DOI: 10.1128/jb.159.3.850-856.1984] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The uptake hydrogenase of chemolithotrophically grown Rhizobium japonicum was purified to apparent homogeneity with a final specific activity of 69 mumol of H2 oxidized per min per mg of protein. The procedure included Triton extraction of broken membranes and DEAE-cellulose and Sephacryl S-200 chromatographies. The purified protein contained two polypeptides separable only by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. They comigrated on native polyacrylamide gels and sucrose density gradients. The molecular weights were ca. 60,000 and 30,000. Densitometric scans of the sodium dodecyl sulfate gels indicated a molar ratio of 1.03 +/- 0.03. Antiserum was developed against the 60-kilodalton polypeptide for use in hydrogenase detection by an enzyme-linked immunosorbent assay. The antiserum did not cross-react with the 30-kilodalton polypeptide. Native gel electrophoresis of Triton-extracted cells grown in the presence of 63Ni showed comigration of the hydrogenase and radioactive Ni.
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