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The SaeRS two-component system dynamically regulates cellular adhesion and invasion during group B Streptococcus infection

ABSTRACT: Group B Streptococcus (GBS) is a pathobiont responsible for invasive infections in neonates and in the elderly. The transition from a commensal to an invasive pathogen relies on the timely regulation of a set of virulence factors. In this study, we characterized the role of the SaeRS two-component system in GBS pathogenesis. Loss-of-function mutations in the SaeR response regulator decrease virulence in mouse models of invasive infection . Transcriptome and in vivo analysis reveal a regulatory system specifically activated during infection to control the expression of only two virulence factors: the PbsP adhesin and the BvaP secreted protein. The in vivo surge in SaeRS-regulated genes is complemented by fine-tuning mediated by the repressor of virulence CovRS system to establish a coordinated response. Constitutive activation of the SaeRS regulatory pathway increases adhesion and invasion of epithelial and endothelial barriers, though at the cost of reduced virulence. In conclusion, SaeRS is a specialized and dynamic system that balances the invasion of host barriers with disease progression.

ORGANISM(S): Streptococcus agalactiae

PROVIDER: GSE269249 | GEO | 2024/07/10

REPOSITORIES: GEO

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A vaginal tract signal detected by the GBS SaeRS system elicits transcriptomic changes and enhances murine colonization.

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