New hybrid bacteriocin with activity agaist foodborne pathogens

BELLOMIO, AUGUSTO; GALVÁN, ADRIANA EMILCE; NAVARRO, SILVIA ADRIANA; CHALÓN, MIRIAM CAROLINA

Córdoba

Congreso; LII Reunión Anual de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular (SAIB); 2016

SAIB

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 different pathogenic strains and determinate the sensitivity of peptide to proteolytic enzymes present in the stomach and intestinal contents.To evaluate the antimicrobial activity, we spread a standardized amount of bacteria uniformly on the surface of a LB agar plate to obtain a bacterial lawn.Then 10 ml of a solution of each bacteriocin were spotted on plates.To determine the sensitivity of the 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 the shapes 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.