Response of a Pseudomonas aeruginosa biofilm community to DNA-damaging chemical agents

Pseudomonas aeruginosa strain RM4440 carries a plasmid-borne fusion of the P. aeruginosa recA gene promoter to a promoterless lux operon from Vibrio fisheri. We tested the response of RM4440 in a biofilm to exposure to a 1-h pulse of each of 17 chemicals known to be toxic to bacteria and other organisms. The induction of light produced from the recA-lux fusion present in RM4440 proved to be sensitive and specific for DNA-damaging chemicals when included in a biofilm environment. This study demonstrates the potential usefulness of this construct for in situ investigation of bacterial communities.