A 65-kilobase pathogenicity island is unique to Philadelphia-1 strains of Legionella pneumophila

Abstract

Nucleotide sequence analysis of an ∼80-kb genomic region revealed an ∼65-kb locus that bears hallmarks of a pathogenicity island. This locus includes homologues of a type IV secretion system, mobile genetic elements, and known virulence factors. Comparative studies with other Legionella pneumophila strains and serogroups indicated that this ∼65-kb locus is unique to L. pneumophila serogroup 1 Philadelphia-1 strains.