Posttranscriptional control of quorum-sensing-dependent virulence genes by DksA in Pseudomonas aeruginosa

Article Article scientifique Article Posttranscriptional control of quorum-sensing-dependent virulence genes by DksA in Pseudomonas aeruginosa eng 2003 author Jude Florence 528927 author Kohler Thilo 0000-0003-4889-9492 23327 author Branny Pavel 511646 author Perron Karl 45679 author Mayer M. P. author Comte Rachel author Van Delden Christian 24088 3558-3566 12775693 0021-9193 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC156223/pdf/1262.pdf Pseudomonas aeruginosa controls the secretion of extracellular virulence factors, including rhamnolipids and LasB elastase, by the las and rhl quorum-sensing systems. Here, we mutated the dksA gene of P. aeruginosa by insertion of an Omega-Hg cassette. The mutant displayed growth rates similar to that of the wild type in rich medium but was impaired in growth in defined minimal medium. Production of rhamnolipids and LasB elastase by the dksA mutant was only 4 and 10%, respectively, of wild-type levels. These defects could be partially complemented by introduction of the plasmid-encoded dksA genes from P. aeruginosa or Escherichia coli. In the dksA mutant, the expression of rhlI was increased early during exponential growth, but expression of other quorum-sensing regulator genes-lasR, lasI, and rhlR-was not affected. Although the transcription of the lasB and rhlAB genes was comparable between the dksA mutant and the wild-type strain in peptone tryptic soy broth medium, we observed reduced translation of both genes in the dksA mutant. Similarly, we found that full translation of lasB and rhlAB genes in E. coli also requires the dksA gene. DksA is therefore a novel regulator involved in the posttranscriptional control of extracellular virulence factor production in P. aeruginosa. Bacterial Proteins/ genetics/metabolism Escherichia coli Proteins/genetics Gene Expression Regulation, Bacterial Genes, Bacterial Genetic Complementation Test Genetic Vectors Glycolipids/ genetics/metabolism Ligases Metalloendopeptidases/ genetics/metabolism Mutagenesis, Insertional Plasmids Protein Biosynthesis Pseudomonas aeruginosa/ genetics/growth & development/metabolism Transcription Factors/genetics/metabolism Virulence/genetics Dewey 616 56 Département de médecine 221 false Journal of bacteriology 185 12 a24fcc23-9901-42da-b51e-411b9efb51bb Article Restricted file1.pdf 359497 application/pdf restrictedAccess Faculté de médecine / Section de médecine clinique / Département de médecine

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Posttranscriptional control of quorum-sensing-dependent virulence genes by DksA in Pseudomonas aeruginosa	Journal of bacteriology			2003	630	0

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Jude, Florence