Identification of Bacteriocin Gene in Lactobacillus acidophilus

Abstract

Lactic acid bacteria have the ability to produce antimicrobial substances such as bacteriocins. They are of great interest to research due to some of the lengthy annals of safe use and the generally considered safe (GRAS) and presumed safety (QPS) status. Bacteriocins are small, hydrophobic, cationic peptides with bacteriostatic or bactericidal activity in various microbes other than the producing strain. The production of bacteriocin depends on its strain and culture optimization. Genes encoding bacteriocin are located in chromosomes or plasmids. This study was carried out to detect the bacteriocin gene in Lactobacillus acidophilus FNCC 0051 and ATCC 4356. Non-lactic acid bacteria (Bifidobacterium bifidum), nuclease-free water, and distilled water are used as the negative control. The DNA extraction was carried out following Agilent Technologies® DNA Extraction Kit with some modifications. Primers used in this study are specific gene primers for acidocin LF221A, and the PCR cycling condition was done based on it. The result of using PCR showed that Lactobacillus acidophilus FNCC 0051 and ATCC 4356 have acidocin LF221A gene. It proved by electrophoresis analysis that the amplicon showed bands with a size less than 100 bp. The conclusion is that Lactobacillus acidophilus in this study contains gene encoding bacteriocin. Vice versa, non-lactic acid bacteria such as Bifidobacterium bifidum does not carry the bacteriocins gene.