Dominant role of paraoxonases in inactivation of the Pseudomonas aeruginosa quorum-sensing signal N-(3-oxododecanoyl)-L-homoserine lactone.

Pseudomonas aeruginosa is an opportunistic bacterium which causes serious infections in immunocompromised and cystic fibrosis patients (10). As with many gram-negative bacteria, P. aeruginosa produces acyl-homoserine lactone (AHL) quorum-sensing (QS) signaling molecules termed autoinducers which allow the single-celled organisms to coordinate their actions (36). N-(3-Oxododecanoyl)-l-homoserine lactone (3OC12-HSL) is a key autoinducer synthesized by P. aeruginosa which regulates the expression of extracellular virulence factors and biofilm formation (5, 36). Rats and mice experimentally infected with P. aeruginosa mutants deficient in the ability to produce or respond to 3OC12-HSL exhibited…