LAUSR

A novel bacteriocin-M1-UVs300, which was produced by Lactobacillus plantarum M1-UVs300, was purified and characterized. Bacteriocin-M1-UVs300 was purified sequentially by an aqueous two-phase system (ATPS) and a Sephadex G-50 gel chromatography assay, combined with reverse phase high-performance liquid chromatography (RE-HPLC). The purification resulted in a 3221.63 IU ml−1 titer with a 20.41- fold purification of the original activity. According to a Tricine-SDS-PAGE analysis, the molecular weight of the bacteriocin-M1-UVs300 was approximately 3.4 kDa. A quantitative analysis of the secondary structure of bacteriocin-M1-UVs300 results showed that it had a major β-sheet content of 52.43%, α-helix of 16.17%, β-turn of 15.27%, and a random coil of 16.12%. A partial sequence, GAKSKYGNVG-, was obtained by N-terminal amino acid sequence analysis. The antimicrobial spectrum of bacteriocin-M1-UVs300 exhibited activity against Gram-positive bacteria and Gram-negative bacteria. In addition, it was relatively heat-resistant, active over a range of pH 2–8, and sensitive to proteolytic enzymes, but it was not sensitive to α-amylase. The additives significantly increased the activity of bacteriocin-M1-UVs300 significantly. These findings indicated that bacteriocin-M1-UVs300, is a novel bacteriocin with a broad inhibitory spectrum, and that it had the potential to act as a natural preservative in the food industry.