Genomic diversity and evolution within the species Streptococcus agalactiae
type: Dataset
description: Streptococcus agalactiae is a leading cause of invasive infections in neonates, and responsible for bovine mastitis. It is also a commensal bacterium adapted to asymptomatic colonization of the mammalian gut and of the genitourinary tract. Here, we report the analysis of a collection of 75 strains of human and animal origin by using serotyping, multilocus sequence typing, whole genome DNA-array hybridizations and sequence comparison of putatively virulence-associated loci. Although the most variable parts of the genome are the previously predicted genomic islands, significant genetic variations were present in the genome backbone. Evolution within genes encoding surface and secreted proteins and those involved in the biosynthesis of different capsular types is mainly due to recombination events leading to the replacement of a locus of several genes or to the allelic exchange of the internal part of a gene. These two processes, which led to a broad diversity of surface protein patterns, are probably involved in the diversity of interactions with the host and its immune system. According to gene content comparisons and phylogeny, recent gene replacements by horizontal gene transfer may occur but are rare events. Although specific gene patterns, with respect to the origin of the strains and the epidemiological characteristics, were not identified, we show that the recently described hypervirulent ST-17 lineage is a homogeneous group. The study highlights for the first time that this lineage contains a specific and conserved set of surface proteins, probably accounting for its high capacity to cause infections in newborns.
issued: 2026-05-10T10:41:57.910913
language: en
modified: 2026-05-10T10:41:57.910917
contact point: Organization
  fn: CCSD
keyword: antigenic-diversity
keyword: evolution
keyword: genome-diversity
keyword: infoeu-reposemanticsarticle
keyword: journal-articles
keyword: sdvmplife-sciences-q-biomicrobiology-and-parasitology
keyword: streptococcus-agalactiae
keyword: vaccine
landing page: Institut Pasteur.

Genomic diversity and evolution within the species Streptococcus agalactiae
type: Distribution
format: HTML
issued: 2026-05-10T10:41:57.925049
modified: 2026-05-10T10:41:57.901984
access URL: https://hal.science/hal-00084225

test_moissonnage_selune
type: Agent