PARTIAL PURIFICATION OF ANTIMICROBIAL PEPTIDES ACTIVE AGAINST FOOD BORNE PATHO- GENS

LANZA L; NAVARRO SA; BELLOMIO A; CHALÓN MC

CABA

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

SAIB SAB

Bacteriocins are small, ribosomally synthesized antimicrobial pep-tides that kill bacteria closely related to the producer strain. Hybridbacteriocins were made by the fusion of genes encoding EnterocinCRL35 (munA), Pediocin PA-1 (pedA) and Microcin V (cvaC) sep-arated by a hinge region. These bacteriocins were constructed inorder to obtain peptides with broad antimicrobial spectrum. The aimof this work was to purified different hybrid bacteriocins and micro-cins available in our laboratory. Microcin E492, Microcin V and Mi-crocin H47 were obtained from supernatants of the producer strains.Hybrid bacteriocins with different hinge regions (Ent35-GGG-Mccv,PedA-GGG-MccV, PedA-GIG-MccV) were purified by disruptionof the producing strains and subsequent precipitation of the pro-teins with 40-50% (NH 4 ) 2 SO 4 . The cellular extracts were loadedonto a C18 chromatography cartridge, eluted with acetonitrile andthen were concentrated. The antimicrobial peptides were found tobe active against different food borne pathogens such as Listeriamonocytogenes, Escherichia coli O: 157, Salmonella enterica ser-ovar pullorum and gallinarum. Serial double dilutions of the partiallypurify peptides were performed. Antibiotic activity units (AU/ml) werecalculated as the reciprocal of the highest dilution showing growthinhibition halo against E. coli MC4100. The antimicrobial peptideshave potential biotechnological applications as food biopreservativeand in the pharmaceutical industry.