Abstract
BackgroundThe 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.ResultsCovS 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.ConclusionsThese 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.
Highlights
The Streptococcus pyogenes two-component signal transduction system CovRS has been described to be important for pathogenesis of this exclusively human bacterial species
S. pyogenes competent cells were prepared in the presence of glycin, mutanolysin and hyaluronidase, as follows: S. pyogenes was grown overnight in 10 ml THY broth supplemented with 20 mM glycin, 5 ml of the pre-culture was added to 45 ml of THY supplemented with glycine (20 mM) and mutanolysin (10 U/ml) for overnight incubation
Comparative sequence analysis of the full genome sequenced serotypes, carried out in order to evaluate the degree of homology between covRS sequences among different GAS serotypes, revealed that covRS is highly conserved in GAS
Summary
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. Successful colonization and persistence within the host relies on sensing and responding to the changes in the environmental conditions These responses are very often mediated by two-component signal transduction regulatory systems (TCS). The first step in GAS infection is the adherence of GAS to epithelia of the skin and respiratory tract, a process that is intensively studied on the molecular level [15,16,17] This phenomenon is supported by host extracellular matrix proteins, such as collagen and fibronectin. The expression profile of the GAS MSCRAMMs is time - and serotype-dependent [16]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
