Complete genome sequence and comparative genomic analysis of an emerging human pathogen, serotype V Streptococcus agalactiae

The 2,160,267 bp genome sequence ofStreptococcusagalactiae, the leading cause of bacterial sepsis, pneumonia, and meningitis in neonates in the U.S. and Europe, is predicted to encode 2,175 genes. Genome comparisons amongS. agalactiae,Streptococcus pneumoniae,Streptococcus pyogenes, and the other completely sequenced genomes identified genes specific to the streptococci and toS. agalactiae. Thesein silicoanalyses, combined with comparative genome hybridization experiments between the sequenced serotype V strain 2603 V/R and 19S. agalactiaestrains from several serotypes using whole-genome microarrays, revealed the genetic heterogeneity amongS. agalactiaestrains, even of the same serotype, and provided insights into the evolution of virulence mechanisms.