| Literature DB >> 10894749 |
M Whiteley1, M R Parsek, E P Greenberg.
Abstract
The LasR-LasI and RhlR-RhlI quorum-sensing systems are global regulators of gene expression in the opportunistic pathogen Pseudomonas aeruginosa. Previous studies suggest that the RhlR-RhlI system activates expression of rpoS. We constructed merodiploid strains of P. aeruginosa containing the native rpoS gene and an rpoS-lacZ fusion. Studies of lacZ transcription in these strains indicated that rpoS was not regulated by RhlR-RhlI. We also generated an rpoS null mutant. This rpoS mutant showed elevated levels of rhlI (but not rhlR) transcription, elevated levels of the RhlI-generated acylhomoserine lactone quorum-sensing signal, and elevated levels of RhlR-RhlI-regulated gene transcription. These findings indicate that there is a relationship between RpoS and quorum sensing, but rather than the RhlR-RhlI system influencing the expression of rpoS, it appears that RpoS regulates rhlI.Entities:
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Year: 2000 PMID: 10894749 PMCID: PMC101961 DOI: 10.1128/JB.182.15.4356-4360.2000
Source DB: PubMed Journal: J Bacteriol ISSN: 0021-9193 Impact factor: 3.490