Disruption of srtA gene in Streptococcus suis results in decreased interactions with endothelial cells and extracellular matrix proteins

Vet Microbiol. 2008 Mar 18;127(3-4):417-24. doi: 10.1016/j.vetmic.2007.08.032. Epub 2007 Sep 18.

Abstract

Streptococcus suis, a major pathogen of swine, is an emerging zoonotic agent which causes meningitis and septic shock. In this study, we investigated the ability of S. suis mutant strain (SRTDeltaA) lacking the sortase A gene (srtA) to interact with host cells and extracellular matrix (ECM) proteins, as well as its virulence in a mouse infection model. We demonstrated that mutant SRTDeltaA had reduced capacity to adhere to and invade porcine brain microvascular endothelial cells compared to the wild-type strain. In addition, mutant SRTDeltaA also showed significantly less adherence to plasma fibronectin, cellular fibronectin and collagen type I. However, disruption of srtA had little effect on the virulence of S. suis in a mouse intraperitoneal model of infection. These results indicate that surface proteins anchored by sortase A are required for a normal level of bacterial binding. However, other factors may also be important for S. suis virulence and interaction with host tissues.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminoacyltransferases / genetics*
  • Animals
  • Bacterial Adhesion / physiology*
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Cell Line
  • Cells, Cultured
  • Collagen / metabolism
  • Cysteine Endopeptidases / genetics*
  • Disease Models, Animal
  • Endothelial Cells / microbiology*
  • Extracellular Matrix Proteins / metabolism*
  • Female
  • Fibronectins / metabolism
  • Humans
  • Mice
  • Mice, Inbred Strains
  • Mutation
  • Protein Binding
  • Streptococcal Infections / microbiology*
  • Streptococcus suis / genetics
  • Streptococcus suis / pathogenicity*
  • Streptococcus suis / physiology
  • Swine
  • Virulence / physiology

Substances

  • Bacterial Proteins
  • Extracellular Matrix Proteins
  • Fibronectins
  • Collagen
  • Aminoacyltransferases
  • sortase A
  • Cysteine Endopeptidases