Determination of Pseudomonas aeruginosa transcriptome induced by oleic acid or its derived oxylipins 10-HOME and 7,10-DiHOME.

Oxygenated unsaturated fatty acids, known as oxylipins, are signaling molecules commonly used for cell-to-cell communication in eukaryotes. However, a role for oxylipins in mediating communication in prokaryotes has not previously been described. Bacteria mainly communicate via quorum sensing (QS) , which involves the production and detection of diverse small molecules termed autoinducers. We showed that oleic acid-derived oxylipins 10-HOME and 7,10-DiHOME produced by Pseudomonas aeruginosa function as autoinducers of a novel quorum sensing system termed Oxylipin-Dependent QS Sytem (ODS). This experiment was designed to determine the genes whose expression is altered by these P. aeruginosa oxylipins. We found that the ODS system controls the cell density-dependent expression of a P. aeruginosa gene subset through the mediation of 10-HOME and 7,10-DiHOME oxylipins. Pseudomonas aeruginosa mRNA profiles of strain PAO1 ΔPA2076 (ΔodsR ) in the absence or presence of oleic acid or its derived oxylipins 10-HOME and 7,10-DiHOME.