1. Carnocin UI49, a potential biopreservative produced by Carnobacterium piscicola: large scale purification and activity against various gram-positive bacteria including Listeria sp
G Stoffels, H G Sahl, A Gudmundsdóttir Int J Food Microbiol. 1993 Dec;20(4):199-210. doi: 10.1016/0168-1605(93)90165-d.
This paper describes a simple purification method for the purification of carnocin UI49, a potential biopreservative produced by Carnobacterium piscicola UI49. The protocol was also applicable for the isolation of nisin Z, which is a biopreservative produced by Lactococcus lactis SIK-83. The protocol consists of only two purification steps, XAD chromatography and cation exchange chromatography. It is quick, easy, and can be used for large scale purification of these lantibiotics. The bactericidal activity of carnocin UI49 against carnobacteria, lactococci and Listeria was compared with that of nisin Z. The carnobacteria showed similar sensitivity towards carnocin UI49 and nisin. The nisin producing L. lactis strains were very sensitive towards carnocin UI49, while the non-producing L. lactis strains were more sensitive to nisin. The Listeria strains were weakly sensitive to carnocin UI49, lower concentrations of nisin were needed to inhibit growth.
2. Purification and characterization of a new bacteriocin isolated from a Carnobacterium sp
G Stoffels, J Nissen-Meyer, A Gudmundsdottir, K Sletten, H Holo, I F Nes Appl Environ Microbiol. 1992 May;58(5):1417-22. doi: 10.1128/aem.58.5.1417-1422.1992.
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 UI49 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 UI49 belongs to the class of bacteriocins termed lantibiotics.
3. Membrane-associated proteins encoded by the nisin gene cluster may function as a receptor for the lantibiotic carnocin UI49
G Stoffels, A Guthmundsdóttir, T Abee Microbiology (Reading). 1994 Jun;140 ( Pt 6):1443-50. doi: 10.1099/00221287-140-6-1443.
Carnocin UI49, a lantibiotic produced by Carnobacterium piscicola shows bactericidal activity against many lactic acid bacteria. This paper describes the results of a study on the mode of action of carnocin UI49. It has previously been observed that nisin-producing Lactococcus lactis subsp. lactis strains are at least 10-fold more sensitive to carnocin UI49 relative to other lactic acid bacteria. Addition of carnocin UI49 to cells of L. lactis subsp. lactis NZ9700 resulted in a dissipation of the membrane potential and a rapid hydrolysis of internal ATP. These results suggest that carnocin UI49 may act at the cytoplasmic membrane. The correlation between production of and/or immunity to nisin and sensitivity to carnocin of L. lactis subsp. lactis strains was further investigated. Several transformed L. lactis subsp. lactis strains carrying a fragment of the nisin gene cluster were tested for their sensitivity to carnocin UI49 and their immunity to nisin. The results suggest that NisP, which is one of the membrane-associated proteins involved in the production of nisin acts as receptor for carnocin UI49. This may facilitate the binding and/or insertion of carnocin UI49 into the cytoplasmic membrane thus increasing its bactericidal activity. Lantibiotic-producing and non-producing mutants of Staphylococcus epidermidis and Lactobacillus sake did not show a difference in sensitivity to carnocin UI49. The proposed receptor-mediated action of carnocin UI49 at the cytoplasmic membrane therefore seems to be specific for the nisin-producing strains.
