Characterization of anti-Listeria innocua. F Bacteriocins Produced by Lactococcus lactis ssp raffinolactis Isolated from Algerian Camel Milk

Abstract

Aims: Our work is focused on the characterization of anti-Listeria innocua. F bacteriocins produced by lactic acid bacteria belonging to the genus Lactococcus isolated from camel milk. Methodology: We tested the bacteriocins activities by diffusion wells method, followed by protease inactivation. The antibacterial peptides are extracted by adsorption/desorption method and then separated on a PAGE-SDS and their activity is detected by the zymogram technique. On the other hand, genetic characterization of these molecules was realized by the plasmid curing using two antibiotics, Rifampicin and Novobiocin. The cure is checked by extraction of the plasmids followed by a migration on an agarose gel. The Bac-mutants obtained underwent testing activity by well diffusion method and by zymogram technique, using as a positive control, wild strains Bac+.