New hybrid bacteriocin whit activity agaist foodborne pathogens

NAVARRO, S.; GALVAN, AE; BELLOMIO, A; CHALON M.C.

Cordoba

Congreso; Reunión Anual de la Sociedad Argentina de Investigaciones en Bioquímica y Biología Molecular; 2016

Sociedad Argentina de Investigaciones en Bioquimica y Biologia Molecular

Bacteriocins are bacterial antimicrobial peptides of ribosomal synthesis active on phylogenetically related organisms. In previous studies we produced a new hybrid peptide named PedA1-GGG-ColV whit broader antimicrobial spectrum. The aim of this work was to evaluate antimicrobial activity against differen tpathogenic strains and determinate the sensitivity of peptide to proteolytic enzymes present in the stomach and intestinal contents. To evaluate the antimicrobial lactivity, we spread a standardized amount of bacteria uniformly on the surface of a LB agar plate to obtain a bacterial lawn. Then 10ml of a solution of each bacteriocin were spotted on plates. To determine the sensitivity of hybrid bacteriocin to proteolytic enzymes, 10 µl of peptide were spotted onto LB plates and 10 µl of proteolytic enzymes solution was placed 1 cm away from the cultured medium drops. The plate was covered with 4 ml of 0.6% agar previously inoculated with the indicator strain. After overnight incubation at 37°C, the growth inhibition zones around the drops of hybrid media were recorded. We interpreted thes hapes of growth inhibition zones around these hybrid as suggesting that digestive enzymes diffuse and decreasing the efficiency of indicator strain growth inhibition.PedA1-GGG-ColV displayed an antibiotic effect on most of the tested strains and result inactivated by digestive enzymes in vitro.