Title: | "A genetic determinant in Streptococcus gordonii Challis encodes a peptide with activity similar to that of enterococcal sex pheromone cAM373, which facilitates intergeneric DNA transfer" |
Author(s): | Vickerman MM; Flannagan SE; Jesionowski AM; Brossard KA; Clewell DB; Sedgley CM; |
Address: | "Department of Periodontics and Endodontics, School of Dental Medicine, University at Buffalo, 223 Foster Hall, Buffalo, New York 14214, USA" |
ISSN/ISBN: | 1098-5530 (Electronic) 0021-9193 (Print) 0021-9193 (Linking) |
Abstract: | "Enterococcus faecalis strains secrete multiple peptides representing different sex pheromones that induce mating responses by bacteria carrying specific conjugative plasmids. The pheromone cAM373, which induces a response by the enterococcal plasmid pAM373, has been of interest because a similar activity is also secreted by Streptococcus gordonii and Staphylococcus aureus. The potential to facilitate intergeneric DNA transfer from E. faecalis is of concern because of extensive multiple antibiotic resistance, including vancomycin resistance, that has emerged among enterococci in recent years. Here, we characterize the related pheromone determinant in S. gordonii and show that the peptide it encodes, gordonii-cAM373, does indeed induce transfer of plasmid DNA from E. faecalis into S. gordonii. The streptococcal determinant camG encodes a lipoprotein with a leader sequence, the last 7 residues of which represent the gordonii-cAM373 heptapeptide SVFILAA. Synthetic forms of the peptide had activity similar to that of the enterococcal cAM373 AIFILAS. The lipoprotein moiety bore no resemblance to the lipoprotein encoded by E. faecalis. We also identified determinants in S. gordonii encoding a signal peptidase and an Eep-like zinc metalloprotease (lspA and eep, respectively) similar to those involved in processing certain pheromone precursors in E. faecalis. Mutations generated in camG, lspA, and eep each resulted in the ablation of gordonii-cAM373 activity in culture supernatants. This is the first genetic analysis of a potential sex pheromone system in a commensal oral streptococcal species, which may have implications for intergeneric gene acquisition in oral biofilms" |
Keywords: | "Amino Acid Sequence DNA, Bacterial/*genetics DNA, Intergenic/*genetics Enterococcus faecalis/genetics Gene Transfer, Horizontal/genetics/physiology Molecular Sequence Data Mutation Oligopeptides/chemistry/genetics/*metabolism Polymerase Chain Reaction Seq;" |
Notes: | "MedlineVickerman, M M Flannagan, S E Jesionowski, A M Brossard, K A Clewell, D B Sedgley, C M eng R01 DE011090/DE/NIDCR NIH HHS/ R29 DE011090/DE/NIDCR NIH HHS/ DE11090/DE/NIDCR NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't 2010/03/18 J Bacteriol. 2010 May; 192(10):2535-45. doi: 10.1128/JB.01689-09. Epub 2010 Mar 16" |