[Distribution and genetic organization of the pathogenicity island XII among the clinical strains of GBS].

Streptococcus agalactiae or group B streptococci (GBS) is the major cause of various diseases of the newborns and the adults. The genome of GBS contains from 14 to 15 mobile genetic elements (pathogenicity islands, PAI). It is well-known that many GBS virulence determinants are localized not in the core genome, but on the pathogenicity islands. The goal of this work was to determine the distribution and genetic organization of PAI XII containing virulence genes sspB1, scpB, lmb among the clinical strains of GBS. 74 clinical strains of GBS were analyzed using PCR with primers corresponding to the genes of the virulence factors located on PAI XII. The pathogenicity island XII was determined only in 22% of the clinical strains. The genetic organization of the island was different between strains. There was no correlation between the presence of PAI and the serotype of GBS.