Division of Research and Development, World Institute of Kimchi, Gwangju, 61755, Republic of Korea.
J Microbiol. 2021 May;59(5):460-466. doi: 10.1007/s12275-021-0513-1. Epub 2021 Apr 28.
To date, all species in the genus Salicibibacter have been isolated in Korean commercial kimchi. We aimed to describe the taxonomic characteristics of two strains, NKC5-3 and NKC21-4, isolated from commercial kimchi collected from various regions in the Republic of Korea. Cells of these strains were rod-shaped, Gram-positive, aerobic, oxidase- and catalase-positive, non-motile, halophilic, and alkalitolerant. Both strains, unlike other species of the genus Salicibibacter, could not grow without NaCl. Strains NKC5-3 and NKC21-4 could tolerate up to 25.0% (w/v) NaCl (optimum 10%) and grow at pH 7.0-10.0 (optimum 8.5) and 8.0-9.0 (optimum 8.5), respectively; they showed 97.1% 16S rRNA gene sequence similarity to each other and were most closely related to S. kimchii NKC1-1 (97.0% and 96.8% similarity, respectively). The genome of strain NKC5-3 was nearly 4.6 Mb in size, with 4,456 protein-coding sequences (CDSs), whereas NKC21-4 genome was nearly 3.9 Mb in size, with 3,717 CDSs. OrthoANI values between the novel strains and S. kimchii NKC1-1 were far lower than the species demarcation threshold. NKC5-3 and NKC21-4 clustered together to form branches that were distinct from the other Salicibibacter species. The major fatty acids in these strains were anteiso-C and anteiso-C, and the predominant menaquinone was menaquinone-7. The polar lipids of NKC5-3 included diphosphatidylglycerol (DPG), phosphatidylglycerol (PG), and five unidentified phospholipids (PL), and those of NKC21-4 included DPG, PG, seven unidentified PLs, and an unidentified lipid. Both isolates had DPG, which is the first case in the genus Salicibibacter. The genomic G + C content of strains NKC5-3 and NKC21-4 was 44.7 and 44.9 mol%, respectively. Based on phenotypic, genomic, phylogenetic, and chemotaxonomic analyses, strains NKC5-3 (= KACC 22040 = DSM 111417) and NKC21-4 (= KACC 22041 = DSM 111418) represent two novel species of the genus Salicibibacter, for which the names Salicibibacter cibarius sp. nov. and Salicibibacter cibi sp. nov. are proposed.
迄今为止，属 Salicibibacter 中的所有种都从韩国商业泡菜中分离得到。本研究的目的是描述从韩国不同地区采集的商业泡菜中分离得到的两个菌株，NKC5-3 和 NKC21-4 的分类特征。这两个菌株的细胞均呈杆状，革兰氏阳性，需氧，氧化酶和接触酶阳性，不运动，嗜盐，耐碱。与属内其他种不同的是，这两个菌株均不能在无 NaCl 的情况下生长。菌株 NKC5-3 和 NKC21-4 分别能耐受高达 25.0%（w/v）NaCl（最适 10%）和 pH7.0-10.0（最适 8.5）和 8.0-9.0（最适 8.5）；它们的 16S rRNA 基因序列相似性均为 97.1%，与 Salicibibacter kimchii NKC1-1 的相似性分别为 97.0%和 96.8%。菌株 NKC5-3 的基因组大小约为 4.6 Mb，包含 4456 个蛋白编码序列（CDS），而 NKC21-4 的基因组大小约为 3.9 Mb，包含 3717 个 CDS。新菌株与 S. kimchii NKC1-1 之间的 OrthoANI 值远低于种的区分阈值。NKC5-3 和 NKC21-4 聚类形成与其他 Salicibibacter 种不同的分支。这些菌株的主要脂肪酸为 anteiso-C 和 anteiso-C，主要的menaquinone 为menaquinone-7。NKC5-3 的极性脂包括二磷脂酰甘油（DPG）、磷脂酰甘油（PG）和五种未鉴定的磷脂（PL），而 NKC21-4 的极性脂包括 DPG、PG、七种未鉴定的 PL 和一种未鉴定的脂。两个分离株都含有 DPG，这在 Salicibibacter 属中是首例。菌株 NKC5-3 和 NKC21-4 的基因组 G+C 含量分别为 44.7 和 44.9 mol%。基于表型、基因组、系统发育和化学分类分析，菌株 NKC5-3（=KACC 22040=DSM 111417）和 NKC21-4（=KACC 22041=DSM 111418）代表 Salicibibacter 属的两个新种，分别命名为 Salicibibacter cibarius sp. nov. 和 Salicibibacter cibi sp. nov.。
