Partial characterization of bacteriocin AMA-K, produced by Lactobacillus plantarum AMA-K isolated from naturally fermented milk from Zimbabwe

Dadih is one of the traditional fermented milk products of West Sumatera. Dadih contain a lot of lactic acid bacteria that acts as a coagulant and preservative. Some lactic acid bacteria also act as a probiotic agent because of characteristics that are resistant to acidic conditions. Some of the main requirements of microbes that can be used as probiotic microbes were resistant to low pH, bile salts, able to colonize, and having antimicrobial activity. Each species of the genus Lactobacillus havedifferent characteristics. This characteristic are influenced by the environment in which the bacteria live. Isolation, identification and characterization of lactic acid bacteria derived from buffalo milk were done. The results of isolated lactic acid bacteria was Lactobacillus plantarum. The characterization of Lactobacillus plantarum indicated that these isolates were able to survive in a concentration of medium containing 0.5% bile salts, resistant to acidic media until pH 2, have antimicrobial activity (inhibit Escherichia coli, Staphylococcus aureus and Enterococcus faecalis).

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

Journal of the Serbian Chemical Society ◽

10.2298/jsc100605060s ◽

2011 ◽

Vol 76 (5) ◽

pp. 699-707 ◽

Cited By ~ 4

Author(s):

Svetlana Seatovic ◽

Jelena Jovanovic-Novakovic ◽

Gordana Zavisic ◽

Zeljka Radulovic ◽

Marija Gavrovic-Jankulovic ◽

...

Keyword(s):

Antimicrobial Activity ◽

Lactobacillus Plantarum ◽

Pathogenic Bacteria ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Proteinase K ◽

Probiotic Bacteria ◽

Partial Characterization ◽

Antimicrobial Substance

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.

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