Title: | "Enterococcal Sex Pheromones: Evolutionary Pathways to Complex, Two-Signal Systems" |
Address: | "Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, USA dunny001@umn.edu. Department of Medical Biochemistry and Biophysics, Umea University, Umea, Sweden" |
ISSN/ISBN: | 1098-5530 (Electronic) 0021-9193 (Print) 0021-9193 (Linking) |
Abstract: | "Gram-positive bacteria carry out intercellular communication using secreted peptides. Important examples of this type of communication are the enterococcal sex pheromone systems, in which the transfer of conjugative plasmids is controlled by intercellular signaling among populations of donors and recipients. This review focuses on the pheromone response system of the conjugative plasmid pCF10. The peptide pheromones regulating pCF10 transfer act by modulating the ability of the PrgX transcription factor to repress the transcription of an operon encoding conjugation functions. Many Gram-positive bacteria regulate important processes, including the production of virulence factors, biofilm formation, sporulation, and genetic exchange using peptide-mediated signaling systems. The key master regulators of these systems comprise the RRNPP (RggRap/NprR/PlcR/PrgX) family of intracellular peptide receptors; these regulators show conserved structures. While many RRNPP systems include a core module of two linked genes encoding the regulatory protein and its cognate signaling peptide, the enterococcal sex pheromone plasmids have evolved to a complex system that also recognizes a second host-encoded signaling peptide. Additional regulatory genes not found in most RRNPP systems also modulate signal production and signal import in the enterococcal pheromone plasmids. This review summarizes several structural studies that cumulatively demonstrate that the ability of three pCF10 regulatory proteins to recognize the same 7-amino-acid pheromone peptide arose by convergent evolution of unrelated proteins from different families. We also focus on the selective pressures and structure/function constraints that have driven the evolution of pCF10 from a simple, single-peptide system resembling current RRNPPs in other bacteria to the current complex inducible plasmid transfer system" |
Keywords: | "Bacterial Proteins/genetics/metabolism Biological Evolution *Conjugation, Genetic Enterococcus faecalis/genetics/*metabolism Gene Expression Regulation, Bacterial Humans Peptides/metabolism Pheromones/*metabolism;" |
Notes: | "MedlineDunny, Gary M Berntsson, Ronnie Per-Arne eng R01 GM049530/GM/NIGMS NIH HHS/ R35 GM118079/GM/NIGMS NIH HHS/ Research Support, N.I.H., Extramural Research Support, Non-U.S. Gov't Review 2016/03/30 J Bacteriol. 2016 May 13; 198(11):1556-1562. doi: 10.1128/JB.00128-16. Print 2016 Jun 1" |