Regulation of the pAD1 sex pheromone response of Enterococcus faecalis by direct interaction between the cAD1 peptide mating signal and the negatively regulating, DNA-binding TraA protein.
The Enterococcus faecalis conjugative plasmid pAD1 (60 kb) encodes a mating response to the recipient-produced peptide sex pheromone cAD1. The response involves two key plasmid-encoded regulatory proteins: TraE1, which positively regulates all or most structural genes relating to conjugation, and TraA, which binds DNA and negatively regulates expression of traE1. In vitro studies that included development of a DNA-associated protein-tag affinity chromatography technique showed that TraA (37.9 kDa) binds directly to cAD1 near its carboxyl-terminal end and, as a consequence, loses its affinity for DNA. Analyses of genetically modified TraA proteins indicated that truncations within the carboxyl-terminal 9 residues significantly affected the specificity of peptide-directed association/dissociation of DNA. The data support earlier observations that transposon insertions near the 3' end of traA eliminated the ability of cells to respond to cAD1.
Fujimoto
S
S
Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, MI 48109, USA.
Clewell
D B
DB
D001425:Bacterial Outer Membrane Proteins / Q000378:metabolism*; D002262:Carboxy-Lyases / Q000378:metabolism*; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D013293:Enterococcus faecalis / Q000378:metabolism*; D036781:Fimbriae Proteins; D015964:Gene Expression Regulation, Bacterial
D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D036781:Fimbriae Proteins; D002262:Carboxy-Lyases; C087194:phenylacrylic acid decarboxylase