Lactobacillus enshiensis sp. nov., a novel arsenic-resistant bacterium

Abstract

A lactic acid bacterial strain, HBUAS57009T, isolated from traditionally fermented food (Zha-Chili) in China, was characterized to clarify its taxonomic status using a polyphasic approach. Strain HBUAS57009T was phylogenetically closely related to Lactobacillus koreensis DCY50T, Lactobacillus fujinensis 218-6T, Lactobacillus mulengensis 112-3T, Lactobacillus cerevisiae TUM BP 140423000-2250T, Lactobacillus tongjiangensis 218-10T and Lactobacillus yonginensis THK-V8T with sequence similarities of 98.6–99.3 %. The genome-to-genome distance and average nucleotide identity values between the genomes of strain HBUAS57009T and type strains of closely related Lactobacillus species were less than 32.0 and 86.0 %, respectively; this is below the threshold for species boundaries. The major cellular fatty acids (>10 %) were C16 : 0, C18 : 1  ω9c and iso-C19 : 0. The G+C content of the genomic DNA of strain HBUAS57009T was 47.8 mol%. Examination of the functional categories of the genome revealed that strain HBUAS57009T could perform both homolactic and heterolactic fermentation processes to produce lactic acid via complete glycolysis and the pentose phosphate pathway. The putative biosynthesis pathway of butane-2,3-diol and acetoin, two important flavour compounds in the food industry, were identified using kegg mapper analysis. Based on its genotypic and phenotypic features, strain HBUAS57009T (=GDMCC 1.1664T=KACC 21424T) is designated as the type strain of a novel species, for which the name Lactobacillus enshiensis sp. nov. is proposed.