Expression of <i>Pseudomonas aeruginosa</i> Virulence Genes Requires Cell-to-Cell Communication

TLDR

Pseudomonas aeruginosa is an opportunistic pathogen that causes infections in immunocompromised hosts and cystic fibrosis patients, and its virulence gene expression depends on cell‑to‑cell communication mediated by a diffusible molecule. Elastase production is regulated by the transcriptional activator LasR, and the lasl gene encodes a component of the biosynthetic pathway for the diffusible autoinducer PAI. Gene lasl is essential for high elastase expression, demonstrating that the PAI autoinducer is required for virulence gene expression.

Abstract

Pseudomonas aeruginosa is an opportunistic human pathogen that causes a variety of infections in immunocompromised hosts and individuals with cystic fibrosis. Expression of elastase, one of the virulence factors produced by this organism, requires the transcriptional activator LasR. Experiments with gene fusions show that gene lasl is essential for high expression of elastase. The lasl gene is involved in the synthesis of a diffusible molecule termed Pseudomonas autoinducer (PAI). PAI provides P. aeruginosa with a means of cell-to-cell communication that is required for the expression of virulence genes and may provide a target for therapeutic approaches.