%0 Journal Article %A Flynn, Sarah %A van Sinderen, Douwe %A Thornton, Gerardine M. %A Holo, Helge %A Nes, Ingolf F. %A Collins, J. Kevin %T Characterization of the genetic locus responsible for the production of ABP-118, a novel bacteriocin produced by the probiotic bacterium Lactobacillus salivarius subsp. salivarius UCC118The GenBank accession number for the sequence reported in this paper is AF408405. %D 2002 %J Microbiology, %V 148 %N 4 %P 973-984 %@ 1465-2080 %R https://doi.org/10.1099/00221287-148-4-973 %K AU, activity unit %K bacterial immunity %K ABC, ATP-binding cassette %K LAB, lactic acid bacteria %K two-peptide bacteriocin %K CFS, cell-free supernatant %K lactic acid bacteria %K Lactobacillus salivarius, Lactobacillus salivarius subsp. salivarius %K AbpIP, induction factor %K Bac, bacteriocin production %I Microbiology Society, %X ABP-118, a small heat-stable bacteriocin produced by Lactobacillus salivarius subsp. salivarius UCC118, a strain isolated from the ileal–caecal region of the human gastrointestinal tract, was purified to homogeneity. Using reverse genetics, a DNA fragment specifying part of ABP-118 was identified on a 10769 bp chromosomal region. Analysis of this region revealed that ABP-118 was a Class IIb two-peptide bacteriocin composed of Abp118α, which exhibited the antimicrobial activity, and Abp118β, which enhanced the antimicrobial activity. The gene conferring strain UCC118 immunity to the action of ABP-118, abpIM, was identified downstream of the abp118β gene. Located further downstream of abp118β, several ORFs were identified whose deduced proteins resembled those of proteins involved in bacteriocin regulation and secretion. Heterologous expression of ABP-118 was achieved in Lactobacillus plantarum, Lactococcus lactis and Bacillus cereus. In addition, the abp118 locus encoded an inducing peptide, AbpIP, which was shown to play a role in the regulation of ABP-118 production. This novel bacteriocin is, to the authors’ knowledge, the first to be isolated from a known human probiotic bacterium and to be characterized at the genetic level. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-148-4-973