Crystal structure of the peptidase domain of Streptococcus ComA, a bifunctional ATP-binding cassette transporter involved in the quorum-sensing pathway.

ABSTRACT: ComA of Streptococcus is a member of the bacteriocin-associated ATP-binding cassette transporter family and is postulated to be responsible for both the processing of the propeptide ComC and secretion of the mature quorum-sensing signal. The 150-amino acid peptidase domain (PEP) of ComA specifically recognizes an extended region of ComC that is 15 amino acids in length. It has been proposed that an amphipathic alpha-helix formed by the N-terminal leader region of ComC, as well as the Gly-Gly motif at the cleavage site, is critical for the PEP-ComC interaction. To elucidate the substrate recognition mechanism, we determined the three-dimensional crystal structure of Streptococcus mutans PEP and then constructed models for the PEP.ComC complexes. PEP had an overall structure similar to the p

SUBMITTER: Ishii S 

PROVIDER: S-EPMC2856284 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature