Identification of ligand specificity determinants in AgrC, the Staphylococcus aureus quorum-sensing receptor.

ABSTRACT: Activation of the agr system, a major regulator of staphylococcal virulence, is initiated by the binding of a specific autoinducing peptide (AIP) to the extracellular domain of AgrC, a classical receptor histidine protein kinase. There are four known agr specificity groups in Staphylococcus aureus, and we have previously localized the determinant of AIP receptor specificity to the C-terminal half of the AgrC sensor domain. We have now identified the specific amino acid residues that determine ligand activation specificity for agr groups I and IV, the two most closely related. Comparison of the AgrC-I and AgrC-IV sequences revealed a set of five divergent residues in the region of the second extracellular loop of the receptor that could be responsible. Accordingly, we exchanged these residu

SUBMITTER: Geisinger E 

PROVIDER: S-EPMC2276371 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature