Objective : To investigate whole genome information of a newly isolatedBifidobacterium animalissubsp. 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 byin vitroexperiments, 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 ofin vitroanalysis 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 enzymes, 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.

There are a large number of natural microbial communities in nature. Different populations inside the consortia expand the performance boundary of a single microbial population through communication and division of labor, reducing the overall metabolic burden and increasing the environmental adaptability. Based on engineering principles, synthetic biology designs or modifies basic functional components, gene circuits, and chassis cells to purposefully reprogram the operational processes of the living cells, achieving rich and controllable biological functions. Introducing this engineering design principle to obtain structurally well-defined synthetic microbial communities can provide ideas for theoretical studies and shed light on versatile applications. This review discussed recent progresses on synthetic microbial consortia with regard to design principles, construction methods and applications, and prospected future perspectives.
Microbial Consortia/genetics* ; Synthetic Biology ; Microbiota ; Models, Theoretical