Susceptibility and adaptive response to bile salts in Propionibacterium freudenreichii: physiological and proteomic analysis.

ABSTRACT: Tolerance to digestive stresses is one of the main factors limiting the use of microorganisms as live probiotic agents. Susceptibility to bile salts and tolerance acquisition in the probiotic strain Propionibacterium freudenreichii SI41 were characterized. We showed that pretreatment with a moderate concentration of bile salts (0.2 g/liter) greatly increased its survival during a subsequent lethal challenge (1.0 g/liter, 60 s). Bile salts challenge led to drastic morphological changes, consistent with intracellular material leakage, for nonadapted cells but not for preexposed ones. Moreover, the physiological state of the cells during lethal treatment played an important role in the response to bile salts, as stationary-phase bacteria appeared much less sensitive than exponentially growing

SUBMITTER: Leverrier P 

PROVIDER: S-EPMC165135 | biostudies-literature | 2003 Jul

REPOSITORIES: biostudies-literature