Bacteriocin

Bacteriocins are proteinogenic toxins secreted by bacteria strains and the growth of other strains of the same or similar types of bacteria inhibit ( inhibit ). It is estimated that 99% of all bacteria produce and excrete at least one bacteriocin. Compared to the usually low molecular weight antibiotics, bacteriocins are peptides or proteins. Your genetic information is encoded on plasmids. Bacteriocins usually have a narrow spectrum of activity, in particular extends this in ways that are similar to the producer organism. Bacteriocins with broad-spectrum activity are nisin from Lactococcus lactis and reutericyclin ( Lactobacillus reuteri ).

Bacteriocins are divided into different categories, such as the nature of the producer strain, the secretion of the active spectrum, the extent of post-translational modification as well as active and resistance mechanism.

Some bacteriocins are of interest to the food industry. So nisin is synthesized from lactic acid bacteria, which can be used as a preservative in various products such as cheese spread.

As the first colicins, bacteriocins have been described in 1925 by André Gratia in Escherichia coli.

Some others, described as bacteriocins with broad-spectrum activity, usually of low molecular substances with antimicrobial properties, such as that produced by Lactobacillus reuteri reuterin are no bacteriocins, since they are not cleaved by proteases and therefore no peptides or proteins.

Examples

• Colicins from E. coli bacteria,
• Duramycin from Streptomyces,
• Lantibiotics from various staphylococci containing lanthionine,
• Halocin
• Nisin from the lactic acid bacterium Lactococcus lactis.
• Sakacin
• Syringacine 4-C and W-1 from Pseudomonas syringae pv syringae