The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
Gene Review

fixJ  -  response regulator FixJ

Sinorhizobium meliloti 1021

Welcome! If you are familiar with the subject of this article, you can contribute to this open access knowledge base by deleting incorrect information, restructuring or completely rewriting any text. Read more.

Disease relevance of fixJ


High impact information on fixJ

  • The fixL product seems to be a transmembrane sensor that modulates the activity of the fixJ product, a cytoplasmic regulator [4].
  • Kanamycin cartridges were inserted into the cloned fixL and fixJ genes and recombined into the host genome [1].
  • Bacterial mutants (fixJ and nifD) and a subset of plant mutants (dnf2, dnf3, dnf4, dnf6, and dnf7) defective for nitrogen fixation induce the above genes [5].
  • In order to identify the FixLJ regulon, gene expression profiles were determined in microaerobic free-living cells as well as during the symbiotic life of the bacterium for the wild type and a fixJ null-mutant strain [6].
  • Attempts at separating the upstream and downstream regions of the nifA promoter so as to maintain fixJ-dependent activity were unsuccessful [7].

Biological context of fixJ

  • Two open reading frames of 1512bp and 613bp were identified as fixL and fixJ [1].
  • Thus FixJ binding sites appear to be preferentially associated with the pSymA replicon, which carries the fixJ gene [8].
  • The genes responsible for sensing and transducing the low oxygen signal, fixL and fixJ, encode proteins (FixL and FixJ, respectively) that are homologous to a large family of bacterial proteins involved in signal transduction, the two component regulatory system proteins [9].

Associations of fixJ with chemical compounds


Regulatory relationships of fixJ

  • A sequence comparison of the -54 to -39 region of nifAp with the upstream sequences of fixKp does not reveal a block of identical nucleotides that could account for the fixJ-dependent microaerobic induction of both promoters [7].

Other interactions of fixJ

  • The remaining seven loci showed fixL- and fixJ-independent induction of expression in response to oxygen limitation [11].


  1. Involvement of fixLJ in the regulation of nitrogen fixation in Azorhizobium caulinodans. Kaminski, P.A., Elmerich, C. Mol. Microbiol. (1991) [Pubmed]
  2. Rhizobium meliloti regulatory gene fixJ activates transcription of R. meliloti nifA and fixK genes in Escherichia coli. Hertig, C., Li, R.Y., Louarn, A.M., Garnerone, A.M., David, M., Batut, J., Kahn, D., Boistard, P. J. Bacteriol. (1989) [Pubmed]
  3. Oxygen regulation of expression of nitrogen fixation genes in Rhizobium meliloti. Agron, P.G., Monson, E.K., Ditta, G.S., Helinski, D.R. Res. Microbiol. (1994) [Pubmed]
  4. A haemoprotein with kinase activity encoded by the oxygen sensor of Rhizobium meliloti. Gilles-Gonzalez, M.A., Ditta, G.S., Helinski, D.R. Nature (1991) [Pubmed]
  5. Plant and bacterial symbiotic mutants define three transcriptionally distinct stages in the development of the Medicago truncatula/Sinorhizobium meliloti symbiosis. Mitra, R.M., Long, S.R. Plant Physiol. (2004) [Pubmed]
  6. FixJ: a major regulator of the oxygen limitation response and late symbiotic functions of Sinorhizobium meliloti. Bobik, C., Meilhoc, E., Batut, J. J. Bacteriol. (2006) [Pubmed]
  7. Mutational analysis of the Rhizobium meliloti nifA promoter. Agron, P.G., Ditta, G.S., Helinski, D.R. J. Bacteriol. (1992) [Pubmed]
  8. FixJ-regulated genes evolved through promoter duplication in Sinorhizobium meliloti. Ferrières, L., Francez-Charlot, A., Gouzy, J., Rouillé, S., Kahn, D. Microbiology (Reading, Engl.) (2004) [Pubmed]
  9. Genetic regulation of nitrogen fixation in Rhizobium meliloti. Cebolla, A., Palomares, A.J. Microbiologia (1994) [Pubmed]
  10. Structural transitions in the FixJ receiver domain. Gouet, P., Fabry, B., Guillet, V., Birck, C., Mourey, L., Kahn, D., Samama, J.P. Structure (1999) [Pubmed]
  11. Isolation and regulation of Sinorhizobium meliloti 1021 loci induced by oxygen limitation. Trzebiatowski, J.R., Ragatz, D.M., de Bruijn, F.J. Appl. Environ. Microbiol. (2001) [Pubmed]
WikiGenes - Universities