Open AccessLactococcin MMFII, a novel class IIa bacteriocin produced by Lactococcus lactis MMFII, isolated from a Tunisian dairy product
Author(s) -
Ferchichi Mounir,
Frère Jacques,
Mabrouk Kamel,
Manai Mohamed
Publication year - 2001
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2001.tb10924.x
Subject(s) - bacteriocin , lactococcus lactis , edman degradation , chemistry , ammonium sulfate precipitation , biochemistry , chromatography , molecular mass , listeria , column chromatography , peptide sequence , bacteria , size exclusion chromatography , biology , listeria monocytogenes , lactic acid , organic chemistry , genetics , gene , antimicrobial , enzyme
A novel bacteriocin, lactococcin MMFII, produced by Lactococcus lactis MMFII isolated from a Tunisian dairy product had been identified. The bacteriocin was purified to homogeneity from fresh overnight M17 broth culture by sulfate ammonium precipitation, cation‐exchange chromatography, sep‐pack chromatography and two steps of reverse‐phase chromatography. The purified bacteriocin was heat stable, pH resistant and protease sensitive. Its amino acid sequence, obtained by Edman degradation, revealed a 37‐amino acid peptide with two cysteine residues in positions 9 and 14 and a calculated mass of 4144.6 Da. Laser desorption mass spectrometry analysis gave a molecular mass of 4142.6, suggesting the presence of a disulfide bond within the purified bacteriocin. Lactococcin MMFII contains the N‐terminal YGNGV consensus motif and is active against Listeria . Thus, it belongs to the class IIa bacteriocins figuring the first example of such a bacteriocin produced by a lactococcal strain.