| Title: | Analysis of the amino acid sequence specificity determinants of the enterococcal cCF10 sex pheromone in interactions with the pheromone-sensing machinery |
| Author(s): | Fixen KR; Chandler JR; Le T; Kozlowicz BK; Manias DA; Dunny GM; |
| Address: | "Department of Microbiology, University of Minnesota, MMC 196, Minneapolis, MN 55455, USA" |
| ISSN/ISBN: | 0021-9193 (Print) 1098-5530 (Electronic) 0021-9193 (Linking) |
| Abstract: | "The level of expression of conjugation genes in Enterococcus faecalis strains carrying the pheromone-responsive transferable plasmid pCF10 is determined by the ratio in the culture medium of two types of signaling peptides, a pheromone (cCF10) and an inhibitor (iCF10). Recent data have demonstrated that both peptides target the cytoplasmic receptor protein PrgX. However, the relative importance of the interaction of these peptides with the pCF10 protein PrgZ (which enhances import of cCF10) versus PrgX is not fully understood, and there is relatively little information about specific amino acid sequence determinants affecting the functional interactions of cCF10 with these proteins in vivo. To address these issues, we used a pheromone-inducible reporter gene system where various combinations of PrgX and PrgZ could be expressed in an isogenic host background to examine the biological activities of cCF10, iCF10, and variants of cCF10 isolated in a genetic screen. The results suggest that most of the amino acid sequence determinants of cCF10 pheromone activity affect interactions between the peptide and PrgX, although some sequence variants that affected peptide/PrgZ interactions were also identified. The results provide functional data to complement ongoing structural studies of PrgX and increase our understanding of the functional interactions of cCF10 and iCF10 with the pheromone-sensing machinery of pCF10" |
| Keywords: | "Amino Acid Sequence Bacterial Proteins/genetics/*metabolism Carrier Proteins/genetics/*metabolism Enterococcus faecalis/*metabolism Gene Expression Regulation, Bacterial Mutation Oligopeptides/genetics/*metabolism Pheromones/genetics/*metabolism;" |
| Notes: | "MedlineFixen, Kathryn R Chandler, Josephine R Le, Thinh Kozlowicz, Briana K Manias, Dawn A Dunny, Gary M eng T32 DE07288/DE/NIDCR NIH HHS/ T32 DE007288/DE/NIDCR NIH HHS/ T32 GM008347/GM/NIGMS NIH HHS/ GM 49530/GM/NIGMS NIH HHS/ R01 GM049530/GM/NIGMS NIH HHS/ T32 GM08347/GM/NIGMS NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't 2006/11/14 J Bacteriol. 2007 Feb; 189(4):1399-406. doi: 10.1128/JB.01226-06. Epub 2006 Nov 10" |
