Quorum sensing differentially regulates Pseudomonas aeruginosa type VI secretion locus I and homologous loci II and III, which are required for pathogenesis.

ABSTRACT: Pseudomonas aeruginosa harbours three type VI secretion (T6S) loci. Although HSI-I has been partially studied, limited knowledge is available on the homologous loci HSI-II and HSI-III. We show that quorum sensing (QS) differentially regulates the expression of genes at all three loci. HSI-I-associated gene expression is suppressed by both the homoserine lactone transcription factor LasR and the 4-hydroxy-2-alkylquinoline (HAQ) transcriptional regulator MvfR. Conversely, both HSI-II and HSI-III loci are positively controlled by LasR and MvfR. PqsE, a key component of the MvfR regulon, is required for the expression of part of HSI-III but not HSI-II, and previously identified inhibitors of HAQ biosynthesis significantly downregulate HSI-II and -III gene expression. Animal and plant infection

SUBMITTER: Lesic B 

PROVIDER: S-EPMC2888175 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature