Kim Subin, Lee Se Hee, Kim Ki Hyun, Yun Misun
Technology Innovation Research Division, World Institute of Kimchi, Gwangju, 61755, Republic of Korea.
Division of Animal Science, Chonnam National University, Gwangju, 61186, Republic of Korea.
J Microbiol. 2024 Dec;62(12):1089-1097. doi: 10.1007/s12275-024-00188-z. Epub 2024 Dec 2.
Two Gram-stain-positive, facultatively anaerobic, non-hemolytic, coccoid-shaped bacterial strains, designated MS01 and MS02, were isolated from cabbage watery kimchi in the Republic of Korea. Cellular growth occurred at 5-25 ℃ (optimum, 20 ℃), pH 5-8 (optimum, pH 7) and in the presence of 0-5% (w/v) NaCl (optimum, 1%). Results of 16S rRNA gene-based phylogenetic analyses showed that strains MS01 and MS02 shared identical sequences, clustered within the Leuconostoc clade in phylogenetic trees, and were most closely related to Leuconostoc inhae IH003 and Leuconostoc gasicomitatum LMG 18811 with sequence similarities of 98.74%. The complete whole-genome sequences of strains MS01 and MS02 measured 2.04-2.06 Mbp and harbored a 50.6 kb plasmid, with DNA G + C contents of 37.7% for both. Based on average nucleotide identities (ANI) and digital DNA-DNA hybridization (dDDH) values, both strains were confirmed to belong to the same species but showed ≤ 85.9% ANI and ≤ 29.9% dDDH values to other Leuconostoc species, indicating that they represent a novel species. Metabolic pathway reconstruction revealed that both strains perform heterolactic acid fermentation, producing lactate, acetate, and ethanol. Chemotaxonomic analyses, including cellular fatty acids, polar lipids, and peptidoglycan amino acid, confirmed the inclusion of both strains within the genus Leuconostoc. Based on the phylogenetic, genomic, and phenotypic characterization, strains MS01 and MS02 were considered to represent a novel species within the genus Leuconostoc, for which the name Leuconostoc aquikimchii sp. nov. is proposed with MS01 (= KACC 23748 = JCM 37028) as the type strain.
从韩国的白菜水泡菜中分离出两株革兰氏阳性、兼性厌氧、非溶血、球状的细菌菌株,命名为MS01和MS02。细胞在5-25℃(最适温度为20℃)、pH 5-8(最适pH为7)以及0-5%(w/v)NaCl(最适浓度为1%)存在的条件下生长。基于16S rRNA基因的系统发育分析结果表明,菌株MS01和MS02具有相同的序列,在系统发育树中聚集在明串珠菌属分支内,与Inhae明串珠菌IH003和嗜水气明串珠菌LMG 18811关系最为密切,序列相似性为98.74%。菌株MS01和MS02的完整全基因组序列长度为2.04-2.06 Mbp,含有一个50.6 kb的质粒,两者的DNA G+C含量均为37.7%。基于平均核苷酸同一性(ANI)和数字DNA-DNA杂交(dDDH)值,证实这两株菌株属于同一物种,但与其他明串珠菌属物种的ANI值≤85.9%,dDDH值≤29.9%,表明它们代表一个新物种。代谢途径重建显示,这两株菌株均进行异型乳酸发酵,产生乳酸、乙酸和乙醇。包括细胞脂肪酸、极性脂质和肽聚糖氨基酸在内的化学分类分析证实,这两株菌株均属于明串珠菌属。基于系统发育、基因组和表型特征,菌株MS01和MS02被认为代表明串珠菌属内的一个新物种,为此提出名为嗜水泡菜明串珠菌(Leuconostoc aquikimchii sp. nov.)的新物种,以MS01(=KACC 23748=JCM 37028)作为模式菌株。