Ren Jianwei, Yu Detao, Li Nianfeng, Liu Shuo, Xu Hang, Li Jiyuan, He Fang, Zou Ling, Cao Zhi, Wen Jianxin
College of Veterinary Medicine, Qingdao Agricultural University, Qingdao 266109, China.
Microorganisms. 2023 Nov 21;11(12):2821. doi: 10.3390/microorganisms11122821.
is an important part of the gut microbiota and a commonly used probiotic. In the present study, to assess the biological characteristics and probiotic properties of derived from mink, we isolated isolate from fecal samples, characterized its biological characteristics, optimized the hydrolysis of casein by its crude extract, and comprehensively analyzed its potential as a probiotic in combination with whole-genome sequencing. Biological characteristics indicate that, under low-pH conditions (pH 2), can still maintain a survival rate of 64.75%; under the conditions of intestinal fluid, gastric acid, and a temperature of 70 °C, the survival rate was increased by 3, 1.15 and 1.17 times compared with the control group, respectively. This shows that it can tolerate severe environments. The results of hydrolyzed casein in vitro showed that the crude bacterial extract of isolate exhibited casein hydrolyzing activity (21.56 U/mL); the enzyme activity increased to 32.04 U/mL under optimized reaction conditions. The complete genome sequencing of was performed using the PacBio third-generation sequencing platform. Gene annotation analysis results revealed that was enriched in several Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathways, and most genes were related to Brite hierarchy pathways (1485-35.31%) and metabolism pathways (1395-33.17%). The egg-NOG annotation revealed that most genes were related to energy production and conversion (185-4.10%), amino acid transport and metabolism (288-6.38%), carbohydrate transport and metabolism (269-5.96%), transcription (294-6.52%), and cell wall/membrane/envelope biogenesis (231-5.12%). Gene Ontology (GO) annotation elucidated that most genes were related to biological processes (8230-45.62%), cellular processes (3582-19.86%), and molecular processes (6228-34.52%). Moreover, the genome of was predicted to possess 77 transporter-related genes. This study demonstrates that has potential for use as a probiotic, and further studies should be performed to develop it as a probiotic additive in animal feed to promote animal health.
是肠道微生物群的重要组成部分，也是一种常用的益生菌。在本研究中，为了评估源自水貂的的生物学特性和益生菌特性，我们从水貂粪便样本中分离出分离株，对其生物学特性进行了表征，优化了其粗提物对酪蛋白的水解作用，并结合全基因组测序全面分析了其作为益生菌的潜力。生物学特性表明，在低pH条件（pH 2）下，仍能保持64.75%的存活率；在肠液、胃酸和70°C温度条件下，存活率分别比对照组提高了3倍、1.15倍和1.17倍。这表明它能耐受恶劣环境。体外酪蛋白水解结果表明，分离株的粗细菌提取物具有酪蛋白水解活性（21.56 U/mL）；在优化的反应条件下，酶活性提高到32.04 U/mL。使用PacBio第三代测序平台对进行了全基因组测序。基因注释分析结果显示，在多个京都基因与基因组百科全书（KEGG）代谢途径中富集，大多数基因与Brite层次途径（1485个，占35.31%）和代谢途径（1395个，占33.17%）相关。egg-NOG注释显示，大多数基因与能量产生和转换（185个，占4.10%）、氨基酸转运和代谢（288个，占6.38%）、碳水化合物转运和代谢（269个，占5.96%）、转录（294个，占6.52%）以及细胞壁/膜/包膜生物合成（23l个，占5.12%）相关。基因本体论（GO）注释表明，大多数基因与生物过程（8230个，占45.62%）、细胞过程（3582个，占19.86%）和分子过程（6228个，占34.52%）相关。此外，的基因组预计拥有77个与转运蛋白相关的基因。本研究表明具有作为益生菌的潜力，应进一步开展研究将其开发为动物饲料中的益生菌添加剂以促进动物健康。
