Pseudomonas aeruginosa Cell-to-Cell Signaling Is Required for Virulence in a Model of Acute Pulmonary Infection

ABSTRACT Cell-to-cell signaling controls many virulence genes in Pseudomonas aeruginosa . We tested the virulence of las and rhl quorum-sensing mutants in neonatal mice. A lasI rhlI double mutant was nearly avirulent, and the respective single mutant strains were reduced in virulence compared with the wild-type strain. Quorum sensing plays a role in P. aeruginosa pneumonia in neonatal mice.