Autoinducer molecules, e.g., N-(3-oxododecanoyl)homoserine lactone, for
Pseudomonas aeruginosa are described. The molecules regulate gene expression
in the bacterium. Therapeutic compositions and therapeutic methods involving analogs
and/or inhibitors of the autoinducer molecules also are described. The molecules
are useful for treating or preventing infection by Pseudomonas aeruginosa.