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Updated: May 11, 2026
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TransFLP — A Method to Genetically Modify Vibrio cholerae Based on Natural Transformation and FLP-recombination
Published on: October 8, 2012
Host Factor Induced Bacterial Extracellular Vesicles Promote Horizontal Gene Transfer in Vibrio cholerae
Dominik Fleischhacker1, Yi-Chi Chen2, Noa Sanchez Gordo1
1Institute of Molecular Biosciences, University of Graz, Graz, Austria.
Journal of Extracellular Vesicles
|May 10, 2026
Summary
Stress-induced bacterial extracellular vesicles (BEVs) from Vibrio cholerae are larger and contain more nucleic acids. These stress-BEVs enhance horizontal gene transfer (HGT) during intestinal colonization, independent of pili.
Area of Science:
- Microbiology
- Bacterial Pathogenesis
- Genetics
Background:
- Vibrio cholerae releases bacterial extracellular vesicles (BEVs) crucial for its lifecycle.
- Previous research focused on BEVs from non-stressed bacteria, primarily outer membrane components.
- Stress conditions encountered during host colonization, like genotoxins and bile, can alter BEV characteristics.
Purpose of the Study:
- To characterize stress-induced bacterial extracellular vesicles (BEVs) released by Vibrio cholerae.
- To investigate the role of these stress-BEVs in horizontal gene transfer (HGT) under intestinal conditions.
Main Methods:
- Vibrio cholerae cultures were exposed to mitomycin C (MMC) or bile to induce stress.
- Characterization of released BEVs, including size, nucleic acid content, and composition.
- Assessed the role of BEVs in horizontal gene transfer (HGT) using antibiotic resistance cassettes and in vitro/in vivo colonization models.
Main Results:
- Stress (MMC or bile) induced the release of larger, nucleic acid-rich BEVs with increased cytoplasmic content.
- Stressor-specific differences in BEV composition and SOS response activation were observed.
- Stress-induced BEVs significantly promoted horizontal gene transfer (HGT) of antibiotic resistance, facilitated by intestinal conditions like bile and proteases.
Conclusions:
- Stress profoundly alters Vibrio cholerae BEV biogenesis and content, creating distinct BEV subtypes.
- BEV-mediated HGT is an important mechanism for genetic exchange in Vibrio cholerae, particularly during host colonization.
- This HGT mechanism is independent of the PilA-pilus but requires the ComEA complex, highlighting novel pathways for bacterial adaptation.
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