Related Experiment Video
Updated: Sep 7, 2025

Applying Advanced In Vitro Culturing Technology to Study the Human Gut Microbiota
Published on: February 15, 2019
Comparative genomic analysis revealed genetic divergence between Bifidobacterium catenulatum subspecies present in
Jiaqi Liu1, Weicheng Li1, Caiqing Yao1
1Key Laboratory of Dairy Biotechnology and Engineering (Inner Mongolia Agricultural University), Ministry of Education; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs; Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering, Inner Mongolia Agricultural University, Hohhot, China.
Background:
The two subspecies of Bifidobacterium catenulatum, B. catenulatum subsp. kashiwanohense and B. catenulatum subsp. catenulatum, are usually from the infant and adult gut, respectively. However, the genomic analysis of their functional difference and genetic divergence has been rare. Here, 16 B. catenulatum strains, including 2 newly sequenced strains, were analysed through comparative genomics.
Results:
A phylogenetic tree based on 785 core genes indicated that the two subspecies of B. catenulatum were significantly separated. The comparison of genomic characteristics revealed that the two subspecies had significantly different genomic sizes (p < 0.05) but similar GC contents. The functional comparison revealed the most significant difference in genes of carbohydrate utilisation. Carbohydrate-active enzymes (CAZyme) present two clustering patterns in B. catenulatum. The B. catenulatum subsp. kashiwanohense specially including the glycoside hydrolases 95 (GH95) and carbohydrate-binding modules 51 (CBM51) families involved in the metabolism of human milk oligosaccharides (HMO) common in infants, also, the corresponding fucosylated HMO gene clusters were detected. Meanwhile, B. catenulatum subsp. catenulatum rich in GH3 may metabolise more plant-derived glycan in the adult intestine.
Conclusions:
These findings provide genomic evidence of carbohydrate utilisation bias, which may be a key cause of the genetic divergence of two B. catenulatum subspecies.
Related Concept Videos
Anatomy of the Intestines
Small Intestines
The small intestine is an ~7 meter-long tube with an inner diameter of just 2.5 cm. Since most nutrients are absorbed here, the inner lining of the...
Bacterial Flora of the Large Intestine
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.
Modern Molecular Taxonomy
Bacterial Phylum Firmicutes
What is Monogastric Digestion?

