Related Experiment Video
Updated: Jul 3, 2026
09:56
Scalable Isolation and Purification of Extracellular Vesicles from Escherichia coli and Other Bacteria
Published on: October 13, 2021
Cytoplasmic membrane vesicles from Clostridioides difficile R20291 are remodeled by osmotic stress
Camila Queraltó1, José Rodríguez1, Fernando Escobar2,3
1Departamento de Ciencias Biológicas, Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile.
Frontiers in Microbiology
|July 2, 2026
Summary
Osmotic stress alters Clostridioides difficile cytoplasmic membrane vesicles (CMVs), changing their size, protein, and lipid content. These modified vesicles show increased association with epithelial cells, impacting host-microbe interactions.
Area of Science:
- Microbiology
- Cell Biology
- Biochemistry
Background:
- Bacterial extracellular vesicles mediate host-microbe interactions by transporting molecules.
- Environmental factors influencing Clostridioides difficile vesicle characteristics are poorly understood.
Purpose of the Study:
- Investigate the impact of osmotic stress on Clostridioides difficile cytoplasmic membrane vesicles (CMVs).
- Analyze changes in CMV physicochemical properties and epithelial cell association.
Main Methods:
- Cultured C. difficile under standard and high-salinity (350 mM NaCl) conditions.
- Isolated and characterized CMVs using electron microscopy, nanoparticle tracking analysis, and biochemical assays.
- Assessed CMV association with HT-29 epithelial cells via microscopy and flow cytometry.
Main Results:
- Osmotic stress altered CMV physicochemical properties, resulting in smaller particle diameters and narrower size distribution.
- NaCl-derived CMVs showed increased protein content and reduced lipid levels.
- Vesicles from osmotic stress conditions exhibited increased association with epithelial cells.
Conclusions:
- Osmotic stress significantly modifies C. difficile CMV size, composition, and epithelial cell interaction.
- Environmental conditions can influence vesicle-mediated interactions, potentially affecting bacterial colonization and pathogenesis.
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