doiSerbia

The partial characterization of the antibacterial peptide bacteriocin G2 produced by the probiotic bacteria Lactobacillus plantarum G2

Šeatović Svetlana L. (Galenika a.d, Belgrade)
Jovanović-Novaković Jelena S. (Galenika a.d, Belgrade)
Zavišić Gordana N. (Galenika a.d, Belgrade)
Radulović Željka Č. (Galenika a.d, Belgrade)
Gavrović-Jankulović Marija Đ. (Faculty of Chemistry, Belgrade)
Jankov Ratko M. (Faculty of Chemistry, Belgrade)

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 аbony. 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.

Keywords: Lactobacillus plantarum, probiotic, bacteriocin