Characterization of Weissella koreensis SK Isolated from Kimchi Fermented at Low Temperature (around 0 °C) Based on Complete Genome Sequence and Corresponding Phenotype

Abstract

This study identified lactic acid bacteria (LAB) that play a major role in kimchi fermented at low temperature, and investigated the safety and functionality of the LAB via biologic and genomic analyses for its potential use as a starter culture or probiotic. Fifty LAB were isolated from 45 kimchi samples fermented at −1.5~0 °C for 2~3 months. Weissella koreensis strains were determined as the dominant LAB in all kimchi samples. One strain, W. koreensis SK, was selected and its phenotypic and genomic features characterized. The complete genome of W. koreensis SK contains one circular chromosome and plasmid. W. koreensis SK grew well under mesophilic and psychrophilic conditions. W. koreensis SK was found to ferment several carbohydrates and utilize an alternative carbon source, the amino acid arginine, to obtain energy. Supplementation with arginine improved cell growth and resulted in high production of ornithine. The arginine deiminase pathway of W. koreensis SK was encoded in a cluster of four genes (arcA-arcB-arcD-arcC). No virulence traits were identified in the genomic and phenotypic analyses. The results indicate that W. koreensis SK may be a promising starter culture for fermented vegetables or fruits at low temperature as well as a probiotic candidate.

A Novel Weissella cibaria Strain UTNGt21O Isolated from Wild Solanum quitoense Fruit: Genome Sequence and Characterization of a Peptide with Highly Inhibitory Potential toward Gram-Negative Bacteria

“…Nonetheless, further studies regarding the cytotoxicity of the peptide as well as its effect on other food spoilage microorganisms are required. In addition, in agreement with other authors, the effect of the peptides produced by lactic acid bacteria during food fermentation and their potential to improve safety of the consumer should be investigated [41][42][43].…”

A novel NADH fluorescence‐based method for identifying and monitoring lactic acid bacteria growths in kimchi

“…LAB belonging to the genera Leuconostoc , Lactobacillus and Weissella are largely responsible for kimchi fermentation (Mun & Chang, 2020). In this study, six stains of kimchi LAB belonging these three genera were used, namely Leuconostoc species, L. mesenteroides TA and L. citreum GR1, Lactobacillus species, Lb.…”

Characterization of the Psychrotrophic Lactic Acid Bacterium Leuconostoc gelidum subsp. aenigmaticum LS4 Isolated from Kimchi Based on Comparative Analyses of Its Genomic and Phenotypic Properties

“…Sixteen kimchi samples stored at 0~10 • C for 1~4 months were collected from different locations in South Korea. Kimchi samples were macerated (hand blender, HHM-600; Hanil, Seoul, Korea) and filtered through a thin cloth, after which kimchi filtrates were diluted and spread onto de Man, Rogosa, and Sharpe (MRS; Difco, Sparks, MD, USA) agar supplemented with 2.0% CaCO 3 [7]. Plates were incubated at 25 • C for 48 h; thereafter, each colony that formed a clear zone on the MRS + 2.0% CaCO 3 agar was simultaneously toothpicked onto two MRS agars and incubated for 48 h at 25 • C or 30 • C. After incubation, colonies that grew at 25 • C but not at 30 • C were tentatively selected as psychrotrophic LAB and subjected to further experiments.…”

“…Various LAB strains were isolated from kimchi with the aim of developing new probiotics or starter cultures for foods [3], but most of these isolates were mesophilic LAB due to the use of a 30 • C incubation temperature in isolation experiments [4][5][6]. However, kimchi is generally fermented at temperatures of less than 10 • C [7]; thus, it can be inferred that LAB that can grow well at low temperatures play an important role in kimchi fermentation.…”