Characterization of bacteriocin-like inhibitory substances (BLIS) from sourdough lactic acid bacteria and evaluation of their in vitro and in situ activity

Molecular approach for the rapid identification, in situ detection and monitoring of sourdough lactobacilli

In situ activity of a bacteriocin-producing Lactococcus lactis strain. Influence on the interactions between lactic acid bacteria during sourdough fermentation

Aims:  To biochemically characterize the bacteriocin produced by Lactococcus lactis ssp. lactis M30 and demonstrate its effect on lactic acid bacteria (LAB) during sourdough propagation. Methods and Results:  A two-peptide bacteriocin produced by L. lactis ssp. lactis M30 was purified by ion exchange, hydrophobic interaction and reversed phase chromatography. Mass spectrometry of the two peptides and sequence analysis of the ltnA2 gene showed that the bacteriocin was almost identical to lacticin 3147. During a 20-day period of sourdough propagation the stability of L. lactis M30 was demonstrated, with concomitant inhibition of the indicator strain Lactobacillus plantarum 20, as well as the …