title: Serotype- and strain- dependent contribution of the sensor kinase CovS of the CovRS two-component system to Streptococcus pyogenes pathogenesis.
abstract: BACKGROUND
  The Streptococcus pyogenes (group A streptococci, GAS) two-component signal transduction system CovRS has been described to be important for pathogenesis of this exclusively human bacterial species. If this system acts uniquely in all serotypes is currently unclear. Presence of serotype- or strain-dependent regulatory circuits and polarity is an emerging scheme in Streptococcus pyogenes pathogenesis. Thus, the contribution of the sensor kinase (CovS) of the global regulatory two-component signal transduction system CovRS on pathogenesis of several M serotypes was investigated.
  
  
  RESULTS
  CovS mutation uniformly repressed capsule expression and hampered keratinocyte adherence in all tested serotypes. However, a serotype- and even strain-dependent contribution on survival in whole human blood and biofilm formation was noted, respectively.
  
  
  CONCLUSIONS
  These data provide new information on the action of the CovS sensor kinase and revealed that its activity on capsule expression and keratinocyte adherence is uniform across serotypes, whereas the influence on biofilm formation and blood survival is serotype or even strain dependent. This adds the CovRS system to a growing list of serotype-specific acting regulatory loci in S. pyogenes.
authors.affiliation: University of Rostock, Medical Faculty, Institute of Medical Microbiology, Virology and Hygiene, Department of Med, Microbiology and Hospital Hygiene, Schillingallee 70, 18055 Rostock, Germany.
authors.forename: Venelina
authors.initials: V
authors.lastname: Sugareva
authors.forename: Regina
authors.initials: R
authors.lastname: Arlt
authors.forename: Tomas
authors.initials: T
authors.lastname: Fiedler
authors.forename: Catur
authors.initials: C
authors.lastname: Riani
authors.forename: Andreas
authors.initials: A
authors.lastname: Podbielski
authors.forename: Bernd
authors.initials: B
authors.lastname: Kreikemeyer
mesh_terms: D001422:Bacterial Adhesion; D016667:Bacterial Capsules / Q000737:chemistry; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms / Q000254:growth & development; D002460:Cell Line; D015964:Gene Expression Regulation, Bacterial; D000071677:Histidine Kinase; D006801:Humans; D006820:Hyaluronic Acid / Q000032:analysis; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D015603:Keratinocytes / Q000382:microbiology; D050296:Microbial Viability; D016254:Mutagenesis, Insertional; D015398:Signal Transduction; D013297:Streptococcus pyogenes / Q000201:enzymology / Q000235:genetics* / Q000472:pathogenicity
chemical_list: D001426:Bacterial Proteins; D047908:Intracellular Signaling Peptides and Proteins; D006820:Hyaluronic Acid; C534547:CovS protein, Streptococcus pyogenes; D000071677:Histidine Kinase