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

A lactic acid bacterial strain, HBUAS57009^T, isolated from traditionally fermented food (Zha-Chili) in China, was characterized to clarify its taxonomic status using a polyphasic approach. Strain HBUAS57009^T was phylogenetically closely related to Lactobacillus koreensis DCY50^T, Lactobacillus fujinensis 218-6^T, Lactobacillus mulengensis 112-3^T, Lactobacillus cerevisiae TUM BP 140423000-2250^T, Lactobacillus tongjiangensis 218-10^T and Lactobacillus yonginensis THK-V8^T with sequence similarities of 98.6-99.3 %. The genome-to-genome distance and average nucleotide identity values between the genomes of strain HBUAS57009^T 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 C_16 : 0, C_18 : 1  ω9c and iso-C_19 : 0. The G+C content of the genomic DNA of strain HBUAS57009^T was 47.8 mol%. Examination of the functional categories of the genome revealed that strain HBUAS57009^T 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 HBUAS57009^T (=GDMCC 1.1664^T=KACC 21424^T) is designated as the type strain of a novel species, for which the name Lactobacillus enshiensis sp. nov. is proposed.