Previous Article | Next Article ![]()
J. Bacteriol., 10 1995, 5567-5573, Vol 177, No. 19
J Nakayama, K Yoshida, H Kobayashi, A Isogai, DB Clewell and A Suzuki
Bacteriocin plasmid pPD1 in Enterococcus faecalis encodes a mating response
to recipient-produced sex pheromone cPD1. Once a recipient acquires pPD1,
transconjugants apparently shut off cPD1 activity in broth culture and no
longer behave as recipients for pPD1. This event is performed by synthesis
of the pheromone inhibitor iPD1 and also by repression of cPD1 production,
the so-called "pheromone shutdown." A 5.4-kb EcoRV-HincII segment of pPD1,
which expressed iPD1 in Escherichia coli, was sequenced and found to be
organized as traC-traB- traA-ipd; each open reading frame is analogous to
that found in other pheromone plasmids, pAD1 and pCF10, and thus is
designated in accordance with the nomenclature in pAD1. The ipd gene
encodes a peptide consisting of 21 amino acids, in which the C-terminal
eight residues correspond to iPD1. The putative TraC product has a strong
similarity to oligopeptide-binding proteins found in other bacterial
species, as do pheromone-binding proteins of pCF10 and pAD1. A strain
carrying traC-disrupted pPD1 required a concentration of cPD1 fourfold
higher than that needed by the wild-type strain for induction of sexual
aggregation. These results suggest that the TraC product contributes to
pheromone sensitivity as a pheromone-binding protein. A strain transformed
with traB-disrupted pPD1 produced a high level of cPD1 similar to that
produced by plasmid-free recipients and underwent self- induction. Thus,
the TraB product contributes to cPD1 shutdown.
Copyright © 1995, American Society for Microbiology
Cloning and characterization of a region of Enterococcus faecalis plasmid pPD1 encoding pheromone inhibitor (ipd), pheromone sensitivity (traC), and pheromone shutdown (traB) genes
Department of Applied Biological Chemistry, University of Tokyo, Japan.
This article has been cited by other articles:
| Appl. Environ. Microbiol. | Infect. Immun. | Eukaryot. Cell |
|---|---|---|
| Mol. Cell. Biol. | J. Virol. | Microbiol. Mol. Biol. Rev. |
| ALL ASM JOURNALS |