Innovative Animal Production System, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8571, Japan.
Nihon Shokuhin Kako Co. LTD, 30, Tajima, Fuji, Shizuoka 417-8530, Japan.
Int J Syst Evol Microbiol. 2024 Sep;74(9). doi: 10.1099/ijsem.0.006517.
Seven novel lactic acid bacterial strains (BF125, BF186, TKL145, YK3, YK6, YK10 and NSK) were isolated from the fresh faeces of Japanese black beef cattle and weanling piglets, spent mushroom substrates, or steeping water of a corn starch production plant. These strains are rod-shaped, Gram-stain-positive, non-motile, non-spore-forming, catalase-negative, cytochrome oxidase-negative, facultatively anaerobic, and homofermentative. Strain BF125 did not produce any gas from glucose; both d- and l-lactate were produced as end-products of glucose (D/L, 40 : 60). Growth occurred at 30-45 °C (optimum, 37 °C), pH 5.0-8.0 (optimum, pH 6.0), and with NaCl concentration of 1.0-3.0% (w/v). The G+C content of genomic DNA of strain BF125 was 37.8 mol% (whole-genome analysis). The major fatty acids were C, C ω9, C cyclopropane 9, 10 and summed feature 10. The 16S rRNA gene in strain BF125 showed high similarity to that of the type strain of (99.93%), and the other isolates were also identified as based on these similarities. A phylogenetic tree based on the core genomes of strains (=54), including the seven isolates, showed that they could be divided into two clusters. Strains YK3, YK6, YK10, and NSK were in the first cluster, along with the type strain DSM 20531, while the second cluster included isolates BF125, BF186, TKL145, and other strains isolated from various animal origins. Phenotypic differences in fermentability were observed for lactose, salicin, and gentiobiose between these two groups. The intergroup digital DNA-DNA hybridization values (72.9-78.6%) and intergroup average nucleotide identity values (95.64-96.92%) were comparable to values calculated using datasets of other valid subspecies of the genus (ex-) . In light of the physiological, genotypic, and phylogenetic evidence, we propose a novel subspecies of , named subsp. subsp. nov. (type strain BF125=MAFF 212522=DSM 115528). Our findings also led to the automatic creation of subsp. subsp. nov. and an emended description of the species .
从日本黑牛肉牛和断奶仔猪的新鲜粪便、废弃蘑菇基质或玉米淀粉生产厂的浸泡水中分离出 7 株新型乳酸菌菌株(BF125、BF186、TKL145、YK3、YK6、YK10 和 NSK)。这些菌株呈杆状,革兰氏阳性,不运动,不产芽孢,过氧化氢酶阴性,细胞色素氧化酶阴性,兼性厌氧,同型发酵。菌株 BF125 不能从葡萄糖产生任何气体;葡萄糖的终产物为 d-和 l-乳酸(D/L,40:60)。生长温度为 30-45°C(最佳温度为 37°C),pH 值为 5.0-8.0(最佳 pH 值为 6.0),NaCl 浓度为 1.0-3.0%(w/v)。菌株 BF125 基因组 DNA 的 G+C 含量为 37.8 mol%(全基因组分析)。主要脂肪酸为 C、Cω9、C 环丙烷 9、10 和总和特征 10。菌株 BF125 的 16S rRNA 基因与模式菌株 (99.93%)的相似度很高,其他分离株也根据这些相似度鉴定为 。基于包括 7 株分离株在内的 54 株 菌株的核心基因组构建的系统发育树表明,它们可分为两个聚类。菌株 YK3、YK6、YK10 和 NSK 与模式菌株 DSM 20531 一起位于第一个聚类中,而第二个聚类包括分离自各种动物来源的菌株 BF125、BF186、TKL145 和其他菌株。这两个群落在乳糖、水杨苷和龙胆二糖的发酵能力上存在表型差异。两个群之间的数字 DNA-DNA 杂交值(72.9-78.6%)和平均核苷酸同一性值(95.64-96.92%)与使用属的其他有效亚种数据集计算的值相当(ex-)。根据生理、遗传和系统发育证据,我们提出了一个新的 属亚种,命名为 subsp. subsp. nov.(模式菌株 BF125=MAFF 212522=DSM 115528)。我们的研究结果还导致了 subsp. subsp. nov. 的自动创建和该物种描述的修正。