Genomic atlas of Bifidobacterium infantis and B. longum informs infant probiotic design.

Study Design

Population: more than 4,000 genomes from 48 countries
Methods: assembled a global genomic atlas of more than 4,000 genomes from 48 countries, increasing representation from LMICs by 12- to 17-fold; high-resolution phylogenomic and functional analyses

Rigorous Journal

Bifidobacterium longum and B. infantis are pioneer colonizers of the neonatal gut and are widely used as probiotics to support infant growth, development, and disease resistance. However, commercial strains derived largely from high-income countries (HICs) may be suboptimal for infants in low- and middle-income countries (LMICs). We assembled a global genomic atlas of more than 4,000 genomes from 48 countries, increasing representation from LMICs by 12- to 17-fold. High-resolution phylogenomic and functional analyses support delineating B. longum and B. infantis as distinct species with divergent functions and epidemiological patterns. B. infantis dominates early-life microbiota in LMICs but is rarely detected in HICs. Natural B. infantis strains show extreme biogeographic stratification and predicted adaptations to local plant-glycan-rich diets and breast-milk-derived substrates, including urea and B vitamins. This genomic resource enables genome-guided selection of geographically matched strains to inform more effective probiotics and precision microbiome therapeutics for diverse infant populations.

Research Insights

Supplement	Dose	Health Outcome	Effect Type	Effect Size	Source
Bifidobacterium infantis	—	Enhanced Disease Resistance	Beneficial	Small	View source Bifidobacterium longum and B. infantis are pioneer colonizers of the neonatal gut and are widely used as probiotics to support infant growth, development, and disease resistance.