Found programs: National Natural Science Foundation of China (No . 82302568) ; Jiangxi Provincial Department of Education Science and Technology Research Project Item— General Item (No . GJJ2203414) ;Natural Science Foundation of Anhui Province (No . 2308085QH283) ; Young Core Teachers Domestic Visiting Project from Educa- tion Department of Anhui Province (No . gxjnfx2023003) ; College Student Innovation and Entrepreneurship Train- ing Project in Anhui Medical University (No . 202310366054) .
Authors：Ding Ruipei 1 , Liu Chengzhong2 , Shi Cancan2 , Zhang Huiyu1 , Dai Yiping2 , Mu Ruxue2 , Li Zilong2 , He Maozhang2 , Li Zhuojun3
Keywords：Bifidobacterium animalis ; isolation and culture; whole genome sequencing; genome analysis; probiot- ics; probiotic gene
DOI：10.19405/j.cnki.issn1000-1492.2025.02.010
〔Abstract〕 Abstract Objective To investigate whole genome information of a newly isolated Bifidobacterium animalis subsp . lactic B4 strain from healthy human feces was analyzed and its probiotic properties . Methods The antimicrobial resistance , hemolytic , gastric acid tolerance and biochemical characteristics of B . animalis B4 were evaluated by in vitro experiments , and its whole genome was sequentially sequenced and functional annotation was performed by next and three-generation sequencing technology. Results Whole genome sequencing of B . animalis B4 showed that its genome size was 1 944 146 bp , with GC content of 60. 49% , no plasmid , and a total of 1 642 genes . The results of in vitro analysis showed that the B . animalis B4 had good probiotic properties , including non-hemolytic and stomach acid resistance . At the same time , the genome results showed that the B . animalis B4 strain did not have toxin and disease-related genes , drug resistance genes were few and the transmission ability was not high , so it had high safety. Gene annotation of KEGG , COG and GO showed that it contained many biological active en- zymes , such as β-galactosidase , L-lactate dehydrogenase and other probiotic genes . Conclusion The B . animalis B4 has good probiotic properties , showing excellent safety at the genetic level , with a probiotic gene sequence .