Previous Article | Next Article ![]()
J. Bacteriol., 07 1997, 4164-4171, Vol 179, No. 13
M Nardi, P Renault and V Monnet
The gene corresponding to the lactococcal oligopeptidase PepF1 (formerly
PepF [V. Monnet, M. Nardi, A. Chopin, M.-C. Chopin, and J.-C. Gripon, J.
Biol. Chem. 269:32070-32076, 1994]) is located on the lactose-proteinase
plasmid of Lactococcus lactis subsp. cremoris NCDO763. Use of the pepF1
gene as a probe with different strains showed that pepF1 is present on the
chromosome of Lactococcus lactis subsp. lactis IL1403, whereas there is a
second, homologous gene, pepF2, on the chromosome of strain NCDO763. From
hybridization, PCR amplification, and sequencing experiments, we deduced
that (i) pepF1 and pepF2 exhibit 80% identity and encode two proteins which
are 84% identical and (ii) pepF2 is included in an operon composed of three
open reading frames and is transcribed from two promoters. The protein,
encoded by the gene located downstream of pepF2, shows significant homology
with methyltransferases. Analysis of the sequences flanking pepF1 and pepF2
indicates that only a part of the pepF2 operon is present on the plasmid of
strain NCDO763, while the operon is intact on the chromosome of strain
IL1403. Traces of several recombination events are visible on the
lactose-proteinase plasmid. This suggests that the duplication of pepF
occurred by recombination from the chromosome of an L. lactis subsp. lactis
strain followed by gene transfer. We discuss the possible functions of PepF
and the role of its amplification.
Copyright © 1997, American Society for Microbiology
Duplication of the pepF gene and shuffling of DNA fragments on the lactose plasmid of Lactococcus lactis
Unite de Recherches de Biochimie et Structure des Proteines, INRA, Jouy en Josas, France.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»