Description and Genomic Characteristics of Weissella fermenti sp. nov., Isolated from Kimchi.

Abstract

A Gram-positive, non-motile, and non-spore-forming lactic acid bacterium, designated as BK2T, was isolated from kimchi, a Korean traditional fermented vegetable food, and the taxonomic characteristics of strain BK2T, along with strain LMG 11983, were analyzed. Both strains optimally grew at 30°C, pH 7.0, and 1.0% NaCl. Cells of both strains were heterofermentative and facultatively anaerobic rods, demonstrating negative reactions for catalase and oxidase. Major fatty acids (>10%) identified in both strains were C18:1 ω9c, C16:0, and summed feature 7 (comprising C19:1 ω6c and/or C19:1 ω7c). The genomic DNA G+C contents of both strains were 44.7 mol%. The 16S rRNA gene sequence similarity (99.9%), average nucleotide identity (ANI; 99.9%), and digital DNA-DNA hybridization (dDDH; 99.7%) value between strains BK2T and LMG 11983 indicated that they are different strains of the same species. Strain BK2T was most closely related to Weissella confusa JCM 1093T and Weissella cibaria LMG 17699T, with 100% and 99.4% 16S rRNA gene sequence similarities, respectively. However, based on the ANI and dDDH values (92.3% and 48.1% with W. confusa, and 78.4% and 23.5% with W. cibaria), it was evident that strain BK2T represents a distinct species separate from W. confusa and W. cibaria. Based on phylogenetic, phenotypic, and chemotaxonomic features, strains BK2T and LMG 11983 represent a novel species of the genus Weissella, for which the name Weissella fermenti sp. nov. is proposed. The type of strain is BK2T (=KACC 22833T=JCM 35750T).