Isolation and Purification of Novel Bacteriocins from Lactobacillus Strains of Vaginal Origin

Abstract

The aim of this study was to isolate and purify bacteriocin compounds from lactobacilli sp of vaginal source origin. Bacteriocins are natural antimicrobial agents produced by lactic acid bacteria. Out of 9 isolates, only 3 strains showed bacteriocin production have checked for potential probiotic properties. All the 3 isolates screened for their survival at pH 2.5 and with 0.3% oxgall. Further autoaggregation properties, coaggregation with pathogen and antimicrobial activity against uropathogenic E. coli were evaluated. JSS6p-54b, JSS8p-48b and JSS9p-58b are bacteriocins obtained from the culture filtrate of isolated strains JSS6, JSS8 and JSS9 from vaginal swab of woman, have been purified to homogeneity using ammonium sulfate precipitation, gel-filtration, and checked on reverse phase highperformance liquid chromatography. SDS-PAGE analysis revealed their masses to be ∼7.0, 8.5 and 6.0 kDa. Maximum production of bacteriocins was reached in the early stationary phase. They were showed a bactericidal mode of action against indicator strain uropathogenic E. coli. The identified properties of bacteriocins indicate that they are having potential application in protection against uropathogens. Keywords: Lactobacillus, Bacteriocin, Autoaggregation, Coaggregation, Gel Filtration chromatography, SDS-PAGE, HPLC, Uropathogens.