Li Pan, Tian Wenni, Jiang Zhuo, Liang Zuanhao, Wu Xueyin, Du Bing
College of Food Science, South China Agricultural University, Guangzhou, China.
Front Microbiol. 2018 Sep 20;9:2216. doi: 10.3389/fmicb.2018.02216. eCollection 2018.
sp. DU-106, a newly isolated member of group, exhibits the predominant ability to produce L-lactic acid. The probiotic potency of test strain revealed its survivability at acidic pH, bile salts and viability in simulated gastric juice . The acute oral toxicity test indicated its no toxicity to laboratory mice . We further determined the complete genome of strain DU-106 to understand genetic basis as a potential probiotic. It has a circular chromosome and three plasmids for a total genome 5,758,208 bp in size with a G + C content of 35.10%. Genes associated with lactate synthesis were found in the DU-106 genome. We also annotated various stress-related, bile salt resistance, and adhesion-related domains in this strain, which likely provide support in exerting probiotic action by enabling adhesion to host epithelial cells and survival under gastrointestinal tract. Moreover, strain DU-106 genome lacks the virulence genes encodes cereulide synthetase, enterotoxin FM, and cytotoxin K. These phenotypic and genomic probiotic potencies facilitate its potential candidate as probiotic starter in food industry.
菌株DU-106是该菌群新分离出的成员,具有产生L-乳酸的主要能力。测试菌株的益生菌效力显示其在酸性pH值、胆盐环境下具有生存能力,且在模拟胃液中具有活性。急性经口毒性试验表明其对实验小鼠无毒性。我们进一步测定了菌株DU-106的完整基因组,以了解其作为潜在益生菌的遗传基础。它有一个环状染色体和三个质粒,基因组总大小为5,758,208 bp,G + C含量为35.10%。在DU-106基因组中发现了与乳酸合成相关的基因。我们还对该菌株中各种与应激、胆盐抗性和黏附相关的结构域进行了注释,这些结构域可能通过使菌株黏附于宿主上皮细胞并在胃肠道中存活,从而为发挥益生菌作用提供支持。此外,菌株DU-106的基因组缺乏编码蜡样芽胞杆菌毒素、肠毒素FM和细胞毒素K的毒力基因。这些表型和基因组方面的益生菌特性使其成为食品工业中益生菌发酵剂的潜在候选菌株。