Related Experiment Video
Updated: Mar 11, 2026
09:26
Identification of Antibacterial Immunity Proteins in Escherichia coli using MALDI-TOF-TOF-MS/MS and Top-Down Proteomic Analysis
Published on: May 23, 2021
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Dynamic interaction between Escherichia coli enterotoxins and bacteriocins.
Dan Liu1, Mengjiao Luo1, Mengyao Li1
1Hunan Provincial Key Laboratory of Animal Intestinal Function and Regulation, Hunan International Joint Laboratory of Animal Intestinal Ecology and Health, College of Life Sciences, Hunan Normal University, Changsha, China.
The FEBS Journal
|March 10, 2026
Summary
Commensal bacteria use bacteriocins to fight pathogens, but toxins produced by pathogens can alter this defense. This study reveals a complex signaling crosstalk that impacts pathogen colonization and suggests new microbiota-based infection control strategies.
Area of Science:
- Microbiology
- Gut Microbiome Research
- Bacterial Pathogenesis
Background:
- The intestinal microbiota is a key defense against pathogens.
- Mechanisms by which pathogens evade or modulate this defense are not fully understood.
Purpose of the Study:
- Investigate microbe-pathogen interactions between commensal and pathogenic Escherichia coli.
- Elucidate the molecular mechanisms of bidirectional regulation via bacteriocin and toxin signaling.
Main Methods:
- Established a coculture model of commensal (E. coli Y18J) and pathogenic (ETEC W25K) E. coli.
- Utilized metagenomic, bioinformatic, and transcriptomic analyses.
- Performed mechanistic investigations using signaling pathway analysis (cGMP, cAMP).
Main Results:
- Commensal bacteriocin (Colicin B/M) and pathogen enterotoxins (ST, LT) exhibit bidirectional signaling.
- ST suppresses, while LT enhances, bacteriocin production.
- LT significantly reduces pathogen colonization in murine models.
- Identified Ligilactobacillus producing bacteriocins that inhibit pathogen colonization.
- Glutamine synthetase regulates bacteriocin-mediated antagonism.
Conclusions:
- Bacterial enterotoxins modulate probiotic antimicrobial activity through dual regulatory mechanisms.
- Uncovered molecular dialog between commensal and pathogenic bacteria.
- Provides a framework for developing microbiota-based strategies against enteric infections.
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