Molecular discrimination of Lactobacillus brevis strains isolated from food products in South Korea using multilocus sequence typing

Lactobacillus brevis plays an important role in the manufacture of fermented foods. The aim of the present study was to know the genetic relationships among L. brevis isolates using multi-locus sequence typing of seven different housekeeping genes. 13 isolates were collected from different food products of South Korea. The results of the sequence analysis indicated 13 different sequence types (STs), each represented by a single strain. Among the seven loci, a total of 83 polymorphic sites were detected. The number of polymorphic sites varied from 4 (rpoB) to 24 (recA), whereas nucleotide diversity per site among the seven genes varied from 0.00161 (rpoB) to 0.01585 (recA). The number of alleles varied from 2 (dnaK) to 13 (recA). SplitsTree recombination was also performed for all seven loci and concatenated sequences. Phylogenetic analysis divided the 13 strains into three major groups based on their relationships. The minimum spanning tree revealed no clear relationship between the and isolation source or location and L. brevis isolates. This is the first genetic diversity study of L. brevis isolates from South Korea.