INVESTIGADORES
RAYA Raul Ricardo
artículos
Título:
Differential roles of the two-component peptides of lactocin 705 in antimicrobial activity.
Autor/es:
CUOZZO SA, CASTELLANO P, SESMA FJ, VIGNOLO GM, RAYA RR.
Revista:
CURRENT MICROBIOLOGY
Editorial:
SPRINGER
Referencias:
Lugar: New York, NY 10013; Año: 2003 vol. 46 p. 180 - 183
ISSN:
0343-8651
Resumen:
Lactobacillus casei CRL705 produces a class IIb bacteriocin, lactocin
705, which relies on the complementary action of two components,
Lac705alpha and Lac705beta. These peptides exert a bactericidal effect
on the indicator strain Lactobacillus plantarum CRL691, with an optimal
Lac705alpha/Lac705beta peptide ratio of 1 to 4. Electron microscopy
studies showed that treated CRL691 cells have their cell wall severely
damaged, with mesosome-like membranous formations protruding into their
cytoplasm. Although less pronounced, a similar effect was also observed
with the Lac705beta peptide alone. Furthermore, Lac705beta increased the
inhibitory action of a diluted supernatant of L. casei CRL705, while
Lac705alpha protected CRL691 cells from inhibition. Both peptides were
required to dissipate the proton motive force (Deltapsi and DeltapH) of
CRL691 cells. These data suggested that of the two components of
lactocin 705, the Lac705alpha peptide is responsible for receptor
recognition, and the Lac705beta peptide is the active component on the
cell membrane of CRL691 cells.