Structural model for covalent adhesion of the Streptococcus pyogenes pilus through a thioester bond.

ABSTRACT: The human pathogen Streptococcus pyogenes produces pili that are essential for adhesion to host surface receptors. Cpa, the adhesin at the pilus tip, was recently shown to have a thioester-containing domain. The thioester bond is believed to be important in adhesion, implying a mechanism of covalent attachment analogous to that used by human complement factors. Here, we have characterized a second active thioester-containing domain on Cpa, the N-terminal domain of Cpa (CpaN). Expression of CpaN in Escherichia coli gave covalently linked dimers. These were shown by x-ray crystallography and mass spectrometry to comprise two CpaN molecules cross-linked by the polyamine spermidine following reaction with the thioester bonds. This cross-linked CpaN dimer provides a model for the covalent attac

SUBMITTER: Linke-Winnebeck C 

PROVIDER: S-EPMC3879542 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature