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Published on: September 30, 2014
Lacticin LC14, a new bacteriocin produced by Lactococcus lactis BMG6.14: isolation, purification and partial
Samar Lasta1, Hadda Ouzari, Nicolas Andreotti
1Laboratoire de Biochimie, CNRS FRE 2738, Faculté de Médecine Nord, Bd Pierre Dramard, 13916 Marseille Cedex 20, France.
Abstract:
A new bacteriocin, lacticin LC14, produced by Lactococcus lactis BMG6.14, was isolated and characterized. It was purified to homogeneity from overnight broth culture by ammonium sulfate precipitation, Sep-Pak chromatography, and two steps of reversed-phase HPLC. Lacticin LC14 showed bactericidal-type antimicrobial activity against several lactic acid bacteria and pathogenic strains including Listeria monocytogenes. It was inactivated by proteinase K and pronase E, but was resistant to papain, lysozyme, lipase and catalase. Lacticin LC14 was heat resistant, stable over a wide range of pH (2-10) and after treatment by solvents and detergents. Its N-terminal end was found unreactive towards Edman sequencing. Based on MALDI-TOF mass spectrometry, its molecular mass was 3333.7 Da. LC14 amino acid composition revealed a high proportion of hydrophobic residues, but no modified ones. LC14 may be able to challenge other well known other bacteriocins in probiotic and therapeutic applications.
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