Bacteriocin gene-mediated ecological adaptation of Bifidobacterium breve in the adult human gut.

2026-04
Cell genomics 6(4)

PubMed: 41421358
DOI: 10.1016/j.xgen.2025.101106

Study Design

Type: Clinical Trial
Population: human intervention
Methods: Comparative genomics; functional assays combining gene knockout, in vitro co-cultivation, and human intervention; phylogenetic and metagenomic analyses of 5,475 lanKC homologs and 6,122 infant gut metagenomes

The ecological persistence of Bifidobacterium breve across life stages reflects adaptive strategies beyond the classical infant- versus adult-type dichotomy, historically attributed to differential nutrient utilization. Here, comparative genomics revealed no major differences in shared carbohydrate-related genes or accessory genome content between infant- and adult-derived strains. Instead, a distinct type III lanthipeptide bacteriocin cluster, lanKC, was specifically detected in adult-derived isolates. Functional assays combining gene knockout, in vitro co-cultivation, and human intervention demonstrated that lanKC enhances strain-level competitive fitness and promotes community stability. Phylogenetic and metagenomic analyses of 5,475 lanKC homologs and 6,122 infant gut metagenomes further suggested a possible early-life acquisition via intra-genus horizontal gene transfer. These findings uncover a previously unrecognized genetic basis underlying B. breve adaptation to the gut environment and support a multi-factorial model in which metabolic flexibility and interference competition jointly sustain bifidobacterial persistence and host-microbe symbiosis throughout life.

Research Insights

Supplement	Dose	Health Outcome	Effect Type	Effect Size	Source
Bifidobacterium breve	—	Improved Stability of Gut Microbiota	Beneficial	Moderate	View source Functional assays combining gene knockout, in vitro co-cultivation, and human intervention demonstrated that lanKC enhances strain-level competitive fitness and promotes community stability.
Bifidobacterium breve	—	Improved Strain-Level Competitive Fitness	Beneficial	Moderate	View source Functional assays combining gene knockout, in vitro co-cultivation, and human intervention demonstrated that lanKC enhances strain-level competitive fitness and promotes community stability.