title: Potential applicability of chymotrypsin-susceptible microcin J25 derivatives to food preservation.
abstract: Microcin J25 (MccJ25) is a 21-residue ribosomally synthesized lariat peptide antibiotic. MccJ25 is active against such food-borne disease-causing pathogens as Salmonella spp., Shigella spp., and Escherichia coli, including E. coli O157:H7 and non-O157 strains. MccJ25 is highly resistant to digestion by proteolytic enzymes present in the stomach and intestinal contents. MccJ25 would therefore remain active in the gastrointestinal tract, affecting normal intestinal microbiota, and this limits the potential use of MccJ25 as a food preservative. In the present paper, we describe a chymotrypsin-susceptible MccJ25 derivative with a mutation of Gly(12) to Tyr that retained almost full antibiotic activity and efficiently inhibited the growth of pathogenic Salmonella enterica serovar Newport and Escherichia coli O157:H7 in skim milk and egg yolk. However, unlike the wild-type MccJ25, the MccJ25(G12Y) variant was inactivated by digestive enzymes both in vitro and in vivo. To our knowledge, our results represent the first example of a rational modification of a microcin aimed at increasing its potential use in food preservation.
authors: Departamento de Bioquímica de la Nutrición, Instituto Superior de Investigaciones Biológicas (Consejo Nacional de Investigaciones Científicas y Técnicas-Universidad Nacional de Tucumán), 4000 San Miguel de Tucumán, Tucumán, Argentina.
authors: María Fernanda
authors: MF
authors: Pomares
authors: Raúl A
authors: RA
authors: Salomón
authors: Olga
authors: O
authors: Pavlova
authors: Konstantin
authors: K
authors: Severinov
authors: Ricardo
authors: R
authors: Farías
authors: Paula A
authors: PA
authors: Vincent
mesh_terms: D019943:Amino Acid Substitution / Q000235:genetics*; D001430:Bacteriocins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D002918:Chymotrypsin / Q000378:metabolism*; D015169:Colony Count, Microbial; D019453:Escherichia coli O157 / Q000187:drug effects; D005519:Food Preservation / Q000379:methods; D005520:Food Preservatives / Q000378:metabolism* / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability; D016297:Mutagenesis, Site-Directed; D019779:Salmonella enterica / Q000187:drug effects
chemical_list: D001430:Bacteriocins; D005520:Food Preservatives; C020411:microcin; D002918:Chymotrypsin