Catch Me If You Can!

Pseudomonas aeruginosa is a Gram-negative opportunistic, often antibiotic resistant and nosocomial, pathogen. Many behavioral responses in P. aeruginosa are regulated by bacterial density-dependent cell-to-cell communication termed quorum sensing. P. aeruginosa relies on three regulons for motility: rhl, pqs, and las systems. Virulence is linked to motility type and is implicated with the human immune response. When preyed upon by Gram-negative Myxococcus xanthus DK1622, prey bacteria such as Escherichia coli and Staphylococcus aureus usually remain in place, even when motile. P. aeruginosa displays an interesting phenotype in that it flees from the advancing front of myxobacterial cells. rhl, pqs, and las transposon mutants of P. aeruginosa will be used in predation assays with M. xanthus DK1622. This will enable us to determine whether one or more of the quorum sensing systems are involved in the regulation of this fleeing phenotype