Purification and amino acid sequence of lactocin 705

JORGE PALACIOS,; VIGNOLO, GRACIELA; EUGENIA FARIAS, MARIA; DE RUIZ HOLGADO, AIDA PESCE; GUILLERMO OLIVER,; FERNANDO SESMA,; GRACIELA MARGARITA VIGNOLO

MICROBIOLOGICAL RESEARCH

Urban & Fisher Verlag

Lugar: Jena; Año: 1999 vol. 154 p. 199 - 204

0944-5013

Lactobacillus casei CRL705, isolated from a dry fermented sausages, produces and antibacterial peptide which is active against Listeria monocytogenes. previous studies have shown that this compound is portentially useful to control food-borne pathogens in ground meat. In view of the potential application of this antimicrobial substance in food fermentation, a detailes biochemical analysis of this peptide is required. In this work, the purification and amino acid sequence of this bacteriocin is presented. The adsorption-desorption pH-dependent property of lactocin 705 was exploited for purification. The active extract was further subjected to RP-HPLC and SDS-PAGE. The active antimicrobial band was electroeluted from SDS-PAGE gel and its amino acid sequence determined. Lactocin 705 had an estimated molecular weight of 3357.80 and an isoelectric point of 10.03. The peptide contains a high ratio of glycine residues and does not show any midified amino acids, like lanthionine or B-methyllantionine. The sequence was unique whrn compared to several databases.