Title: | A novel double-tryptophan peptide pheromone controls competence in Streptococcus spp. via an Rgg regulator |
Author(s): | Mashburn-Warren L; Morrison DA; Federle MJ; |
Address: | "Center for Pharmaceutical Biotechnology, College of Pharmacy, The University of Illinois at Chicago, Chicago, IL 60607, USA" |
DOI: | 10.1111/j.1365-2958.2010.07361.x |
ISSN/ISBN: | 1365-2958 (Electronic) 0950-382X (Print) 0950-382X (Linking) |
Abstract: | "All streptococcal genomes encode the alternative sigma factor SigX and 21 SigX-dependent proteins required for genetic transformation, yet no pyogenic streptococci are known to develop competence. Resolving this paradox may depend on understanding the regulation of sigX. We report the identification of a regulatory circuit linked to the sigX genes of mutans, pyogenic, and bovis streptococci that uses a novel small, double-tryptophan-containing sigX-inducing peptide (XIP) pheromone. In all three groups, the XIP gene (comS), and sigX have identical, non-canonical promoters consisting of 9 bp inverted repeats separated from a -10 hexamer by 19 bp. comS is adjacent to a gene encoding a putative transcription factor of the Rgg family and is regulated by its product, which we designate ComR. Deletion of comR or comS in Streptococcus mutans abolished transformability, as did deletion of the oligopeptide permease subunit oppD, suggesting that XIP is imported. Providing S. mutans with synthetic fragments of ComS revealed that seven C-terminal residues, including the WW motif, cause robust induction of both sigX and the competent state. We propose that this circuit is the proximal regulator of sigX in S. mutans, and we infer that it controls competence in a parallel way in all pyogenic and bovis streptococci" |
Keywords: | "Amino Acid Sequence Bacterial Proteins/genetics/*metabolism Base Sequence *Gene Expression Regulation, Bacterial *Genes, Regulator Molecular Sequence Data Peptides/chemistry/*metabolism Pheromones/chemistry/*metabolism Promoter Regions, Genetic Sigma Fact;" |
Notes: | "MedlineMashburn-Warren, Lauren Morrison, Donald A Federle, Michael J eng R00 GM080539/GM/NIGMS NIH HHS/ R01 AI091779/AI/NIAID NIH HHS/ HHMI/Howard Hughes Medical Institute/ R00GM80539/GM/NIGMS NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't England 2010/10/26 Mol Microbiol. 2010 Nov; 78(3):589-606. doi: 10.1111/j.1365-2958.2010.07361.x. Epub 2010 Sep 14" |