The aim of this study was the partial characterization of the antimicrobial
peptide bacteriocin G2 produced by probiotic bacteria Lactobacillus
plantarum G2, which was isolated from a clinical sample of a healthy person.
Antimicrobial substance was secreted in the supernatant of an L. plantarum
G2 culture, and showed a diverse spectrum of antimicrobial activity of all
the tested strains of the genera Lactobacillus and the pathogenic bacteria
Staphylococcus aureus and Salmonella ?bony. Isoelectric focusing revealed
that bacteriocin G2 is a cationic peptide (pI about 10) with a molecular
mass of 2.2 kDa according to tricine-sodium dodecyl sulphate-polyacrylamide
gel electrophoresis, SDS-PAGE. The antimicrobial activity of bacteriocin G2
was diminished by the proteolytic action of trypsin and proteinase K.
Bacteriocin G2 preserved its biological activity in the temperature range
40-60?C (15 min), which was lost at 80?C. Bacteriocin G2 was stable in the
pH range 2-9, while treatment with 1 % Tween 80 and 1 % urea resulted in
increased antimicrobial activity. The probiotic strain L. plantarum G2
produces the antimicrobial substance proteinaceous in nature with
bacteriocin characteristics. Bacteriocin production is one of the key
properties of probiotic bacteria with clinical potential as anti-infective
agents, which will increase the likelihood of its in vivo efficacy.
Partial characterization of bacteriocin-like substance produced by probiotic Lactobacillus plantarum F12 isolated from Algerian children faeces
