Influence of the pqs genes on Pseudomonas quorum sensing. Pseudomonas aeruginosa PAO1

We used a transcriptomics approach to test the hypothesis that reductive evolution in the PAO1 QS regulon can be explained by a null mutation in pqsR, the gene encoding the transcriptional activator of the pqs operon. We found that PqsR had little influence on the AHL QS regulon. This was a surprising finding because the last gene in the PqsR-dependent pqs operon, pqsE, codes for a protein, which physically interacts with RhlR and this interaction is required for full RhlR-dependent activation of some genes.