Nucleotide sequence of the rpoN gene and characterization of two downstream open reading frames in Pseudomonas aeruginosa.
AUTOR(ES)
Jin, S
RESUMO
The rpoN gene of Pseudomonas aeruginosa is required for the expression of a number of diverse genes, ranging from several classes of bacterial adhesins to enzymes for amino acid biosynthesis. The nucleotide sequence of the rpoN gene and its flanking region has been determined. The deduced amino acid sequence of the rpoN product is highly homologous to sequences of RpoN proteins of other microorganisms. Moreover, two open reading frames (ORF1 and ORF2) encoding peptides of 103 and 154 amino acids long, respectively, were found downstream of the rpoN gene. These two ORF products have a high degree of amino acid sequence homology with products of similar ORFs located adjacent to the rpoN genes in other microorganisms. Mutations in either ORF lead to a significant increase in P. aeruginosa generation time when propagated on minimal medium. These mutations had no effect on the expression of pilin or flagellin genes, whose expression depends on RpoN. Complementation analysis showed that the two ORFs are in the same transcriptional unit and the growth defects of the two ORF mutants on minimal medium are due to mutational effects on ORF2. The adverse effect of the ORF mutations on the growth of P. aeruginosa in minimal media can be suppressed by the addition of glutamine but not arginine, glutamate, histidine, or proline. Since rpoN mutants of P. aeruginosa display this same amino acid requirement for growth, the ORF2 product very likely functions as a coinducer of some but not all of the RpoN-controlled genes.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=205195Documentos Relacionados
- Nucleotide and deduced amino acid sequence of the RpoN sigma-factor of Pseudomonas putida.
- Differential Roles of the Pseudomonas aeruginosa PA14 rpoN Gene in Pathogenicity in Plants, Nematodes, Insects, and Mice
- The Rhizobium etli rpoN Locus: DNA Sequence Analysis and Phenotypical Characterization of rpoN, ptsN, and ptsA Mutants
- FleQ, the Major Flagellar Gene Regulator in Pseudomonas aeruginosa, Binds to Enhancer Sites Located Either Upstream or Atypically Downstream of the RpoN Binding Site
- The rpoN gene product of Pseudomonas aeruginosa is required for expression of diverse genes, including the flagellin gene.