title: Purification and Partial Characterization of Lacticin 481, a Lanthionine-Containing Bacteriocin Produced by Lactococcus lactis subsp. lactis CNRZ 481.
abstract: Lacticin 481, a bacteriocin produced during the growth of Lactococcus lactis subsp. lactis CNRZ 481, was purified sequentially by ammonium sulfate precipitation, gel filtration, and preparative and analytical reversed-phase high-pressure liquid chromatography. Ammonium sulfate precipitations resulted in a 455-fold increase in total lacticin 481 activity. The entire purification protocol led to a 107, 506-fold increase in the specific activity of lacticin 481. On the basis of its electrophoretic pattern in sodium dodecyl sulfate-polyacrylamide gels, lacticin 481 appeared as a single peptide band of 1.7 kDa. However, dimers of 3.4 kDa also exhibiting lacticin activity were detected. Derivatives of the lacticin-producing strain which did not produce lacticin 481 (Bac) were sensitive to this bacteriocin (Bac) and failed to produce the 1.7-kDa band. Amino acid composition analysis of purified lacticin 481 revealed the presence of lanthionine residues, suggesting that lacticin 481 is a member of the lantibiotic family of antimicrobial peptides. Seven residues (K G G S G V I) were sequenced from the N-terminal portion of lacticin 481, and these did not shown any homology with nisin or other known bacteriocin sequences.
authors.affiliation: Station de Recherches Laitières. INRA. 78352 Jouy-en-Josas Cedex. France, and Department of Food Science. Southeast Dairy Foods Research Center. North Carolina State University. Raleigh. North Carolina 27695-7624.
authors.forename: J C
authors.initials: JC
authors.lastname: Piard
authors.forename: P M
authors.initials: PM
authors.lastname: Muriana
authors.forename: M J
authors.initials: MJ
authors.lastname: Desmazeaud
authors.forename: T R
authors.initials: TR
authors.lastname: Klaenhammer