BioMed Central Microbiology
Vibrio Pathogenicity Island-2 (VPI-2) is a 57 kb region present in choleragenic V. cholerae isolates that is required for growth on sialic acid as a sole carbon source. V. cholerae non-O1/O139 pathogenic strains also contain VPI-2, which in addition to sialic acid catabolism genes also encodes a type 3 secretion system in these strains. VPI-2 integrates into chromosome 1 at a tRNA-serine site and encodes an integrase intV2 (VC1758) that belongs to the tyrosine recombinase family. ntV2 is required for VPI-2 excision from chromosome 1, which occurs at very low levels, and formation of a non-replicative circular intermediate.
Almagro-Moreno, Salvador; Napolitano, Michael G.; and Boyd, E. Fidelma, "Excision Dynamics of Vibrio Pathogenicity Island-2 from Vibrio Cholerae: Role of a Recombination Directionality Factor VefA" (2010). Open Dartmouth: Faculty Open Access Articles. 650.