Purification and characterization of a new bacteriocin isolated from a Carnobacterium sp

Abstract

A bacteriocin-producing Carnobacterium sp. was isolated from fish. The bacteriocin, termed carnocin UI49, was purified to homogeneity by a four-step purification procedure, including hydrophobic interaction chromatography and reverse-phase chromatography. Carnocin U149 has a bactericidal mode of action. It was shown to be heat tolerant and stable between pH 2 and 8. At pH above 8, carnocin UI49 was rapidly inactivated. Amino acid analysis revealed a composition of about 35 to 37 amino acids in addition to an unidentified peak which migrates at the position of lanthionine. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis suggests a molecular weight of about 4,500 to 5,000. Mass spectrometry gave a molecular weight of 4,635, which is about 1,000 larger than that calculated from the amino acid analysis data. Performic acid oxidation of carnocin UI49, followed by amino acid hydrolysis, revealed the presence of cysteic acid. The sequence of the first seven amino acid residues was determined to be N-Gly-Ser-Glu-Ile-Gln-Pro-Arg. After the seventh amino acid, carnocin UI49 was not available for further Edman degradation. The results suggest that carnocin U149 belongs to the class of bacteriocins termed lantibiotics.

Isolation and characterization of a new bacteriocin from Lactobacillus gasseri KT7

“…During chromatography on the CM-Sephadex C-25 cationexchange column, an additional 23% loss of the initial bacteriocin activity was observed. Cation-exchange chromatography has been used extensively for bacteriocin puri®cation (Holo et al 1991;Mortvedt et al 1991;Stoffels et al 1992), although successful application on an anion exchanger has also been reported (Bhunia et al 1988). In general, many lactic bacteriocins are cationic, hydrophobic peptides possessing high isoelectric points, like lactococcin A with a pI of 9Á2 (Holo et al 1991).…”

Coagulin, a bacteriocin-like inhibitory substance produced by Bacillus coagulans I4

“…Four major classes of bacteriocins are produced by LAB: I, lantibiotics; II, small heat-stable peptides; III, large heat-labile proteins and IV, complex proteins that additionally require carbohydrate or lipid moieties for bacteriocin activity (Klaenhammer 1993). Other Gram-positive bacteria, such as Staphylococcus aureus (Jung and Sahl 1991), Carnobacterium piscicola (Stoffels et al 1992), Streptococcus pyogenes (Jack et al 1994) and Enterococcus faecalis (Maisnier-Patin et al 1996), also produce antibacterial peptides. Within the genus Bacillus, bacteriocins or bacteriocin-like inhibitory substances (BLIS) have been reported from Bacillus subtilis (Jansen and Hirschmann 1944), B. thuringiensis (De Borjac et al 1974), B. stearothermophilus (Shafia et al 1966), B. licheniformis (Bradley 1967), B. megaterium (Ivanovics 1962), B. thermoleovorans (Novotny et al 1992) and B. cereus (Naclerio et al 1993).…”

Genetics of bacteriocins produced by lactic acid bacteria

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Lactic acid bacteria produce a variety of bacteriocins that have recently come under detailed investigation. The biochemical and genetic characteristics of these antimicrobial proteins are reviewed and common elements are discussed bclwecn the different classes of bacteriocins produced by these Gram-positive bacteria.[38][66,90] [87,88] a Mr determined by mass spectroscopy. b Mr estimated by SDS-PAGE.

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“…l,antibiotics produced by lAB l.antibiotics are produced predominantly by (}ran>positive bacteria and in recent years have bccn subjected to extensive biochemical and genetic characterization (for review see [4]). In addition to nisin A and nisin Z [86], three new [antibiotics have been discovered or proposed: lacticin 481 produced by L. lactis subsp, lactis [35,36,37], carnocin U149 produced by Carnobacterium piscicola [87,88], and lactocin S produced by Lb. sake [66,90].…”