Hybrid polyketide-nonribosomal peptide gene clusters of Legionella pneumophila targeted for mutagenesis. PRISM identified three hybrid PKS-NRPS gene clusters in the genome of L. pneumophila LP02, roughly defined as lpg1936-lpg1943, lpg2177-lpg2186, and lpg2225-lpg2232. Ketosynthases in each gene cluster were insertionally inactivated by insertion of a kanamycin resistance gene, disrupting expression of lpg1939, lpg2186, and lpg2228 (red).