A Lactococcus lactis subsp. lactis strain that can sense the bacteriocin nisin and transduce the signal into bioluminescence was constructed. By using this strain, a bioassay based on bioluminescence was developed for quantification of nisin, for detection of nisin in milk, and for identification of nisin-producing strains. As little as 0.0125 ng of nisin per ml was detected within 3 h by this ...

The lantibiotic nisin is a small 3.4 kDa antimicrobial peptide, which acts against Gram-positive bacteria in the nmol/L range. Nisin is produced and secreted by several Lactococcus lactis strains to ensure advantages against other bacteria in their habitat. Nisin contains five specific lanthionine rings of which the first two are important for Lipid II binding and the last two are crucial for t...

The bacteriocin nisin is produced only by some strains of Lactococcus lactis, and to date production in other lactic acid bacteria has not been achieved. Enterococcus sp. strain N12beta is a nisin-immune transconjugant obtained from a nisin-producing donor (L. lactis ATCC 11454) and a dairy recipient (Enterococcus sp. strain S12beta), but it does not produce nisin. In this study, using PCR ampl...

The lantibiotic nisin has previously been reported to inhibit the outgrowth of spores from several Bacillus species. However, the mode of action of nisin responsible for outgrowth inhibition is poorly understood. By using B. anthracis Sterne 7702 as a model, nisin acted against spores with a 50% inhibitory concentration (IC(50)) and an IC(90) of 0.57 microM and 0.90 microM, respectively. Viable...

Nisin is a cationic antimicrobial peptide that belongs to the group of lantibiotics. It is thought to form oligomeric pores in the target membrane by a mechanism that requires the transmembrane electrical potential delta psi and that involves local pertubation of the lipid bilayer structure. Here we show that nisin does not form exclusively voltage-dependent pores: even in the absence of a delt...

Nisin is the most prominent and applied bacteriocin that serves as a model for class I lantibiotics. The nisin leader peptide importantly determines interactions between precursor nisin and its modification enzymes NisB and NisC that mature nisin posttranslationally. NisB dehydrates serines and threonines, while NisC catalyzes the subsequent coupling of the formed dehydroamino acids to form lan...

Just before the discovery of penicillin by Fleming, reports in the literature appeared that described potent antimicrobial substances produced by lactic acid bacteria. It was found that these substances were specifically active against a wide range of other gram-positive bacteria. These characteristics meant that these compounds were attractive candidates for application in either food preserva...

Nisin is a pore-forming antimicrobial peptide. The capacity of nisin to induce transmembrane movement of a fluorescent phospholipid in lipid vesicles was investigated. Unilamellar phospholipid vesicles that contained a fluorescent phospholipid (1-acyl-2-(6-[(7-nitro-2-1, 3-benzoxadiazol-4-yl)amino]caproyl)-sn-glycero-3-phosphocholine) in the inner leaflet of the bilayer were used. Nisin-induced...

The nisin gene cluster nisABTCIPR of Lactococcus lactis, located on a 10-kbp DNA fragment of the nisin-sucrose transposon Tn5276, was characterized. This fragment was previously shown to direct nisin-A biosynthesis and to contain the nisP and nisR genes, encoding a nisin leader peptidase and a positive regulator, respectively [van der Meer, J. R., Polman, J., Beerthuyzen, M. M., Siezen, R. J., ...

The structural gene for the precursor of the peptide antibiotic nisin was isolated and characterized. As with other lanthionine-containing antibiotics, nisin is synthesized as a pre-propeptide which undergoes post-translational modification to generate the mature antibiotic. The sequence data obtained agreed with those of precursor nisin genes isolated by other workers from different Lactococcu...