Linked Life Data

2000090

Source:http://linkedlifedata.com/resource/pubmed/id/2000090

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1991-4-8
pubmed:databankReference
pubmed:abstractText
The cloning, sequencing and mutational analysis of the Bradyrhizobium japonicum symbiotic nitrogen fixation genes fixL and fixJ are reported here. The two genes were adjacent and probably formed an operon, fixLJ. The predicted FixL and FixJ proteins, members of the two-component sensor/regulator family, were homologous over almost their entire lengths to the corresponding Rhizobium meliloti proteins (approx. 50% identity). Downstream of the B. japonicum fixJ gene was found an open reading frame with 138 codons (ORF138) whose product shared 36% homology with the N-terminal part of FixJ. Deletion and insertion mutations within fixL and fixJ led to a loss of approximately 90% wild-type symbiotic nitrogen fixation (Fix) activity, whereas an ORF138 mutant was Fix+. In fixL, fixJ and ORF138 mutant backgrounds, the aerobic expression of the fixR-nifA operon was not affected. NifA itself did not regulate the expression of the fixJ gene. Thus, the B. japonicum FixL and FixJ proteins were neither involved in the regulation of aerobic nifA gene expression nor in the anaerobic NifA-dependent autoregulation of the fixRnifA operon, rather they appeared to control symbiotically important genes other than those whose expression was dependent on the NifA protein. The fixL and fixJ mutant strains were unable to grow anaerobically with nitrate as the terminal electron acceptor. Therefore, some of the FixJ-dependent genes in B. japonicum may be concerned with anaerobic respiration.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0026-8925
pubmed:author
pubmed:issnType
Print
pubmed:volume
225
pubmed:geneSymbol
fixJ, fixL
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
38-48
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
The regulatory status of the fixL- and fixJ-like genes in Bradyrhizobium japonicum may be different from that in Rhizobium meliloti.
pubmed:affiliation
Mikrobiologisches Institut, Eidgenössische Technische Hochschule, ETH-Zentrum, Zürich, Switzerland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't