Characterization of the determinant (traB) encoding sex pheromone shutdown by the hemolysin/bacteriocin plasmid pAD1 in Enterococcus faecalis.

pAD1 is a hemolysin/bacteriocin plasmid originally identified in Enterococcus faecalis DS16. It encodes a mating response to a peptide sex pheromone, cAD1, secreted by recipient bacteria. Once pAD1 is acquired, production of the pheromone ceases--a trait related in part to a determinant designated traB. Here we report the nucleotide sequence of traB and the position of several transposon insertions resulting in the characteristic self-induction phenotype. The deduced product has a mass of 43.7 kDa with the C-terminal third consisting primarily of hydrophobic amino acid residues.