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Scalable Isolation and Purification of Extracellular Vesicles from Escherichia coli and Other Bacteria
Published on: October 13, 2021
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A Simplified Method for the Isolation of Extracellular Vesicles from Probiotic Bacteria and Their Characterization
Harshal Sawant1, Ji Bihl1, Alip Borthakur1,2
1Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25701, USA.
International Journal of Molecular Sciences
|February 13, 2025
Summary
Researchers developed a standardized protocol for isolating extracellular vesicles (EVs) from probiotic bacteria. Ultracentrifugation yielded more EVs than precipitation, with Escherichia coli Nissle releasing more than Lactobacillus acidophilus.
Area of Science:
- Microbiology
- Nanotechnology
- Biotechnology
Background:
- Probiotic bacteria benefit gut health, but dysbiosis decreases beneficial bacteria.
- Probiotic-derived extracellular vesicles (EVs) mediate host health effects and gut microbiota communication.
- Standardized EV isolation protocols are needed for consistent pre-clinical research.
Purpose of the Study:
- To develop and standardize a protocol for isolating extracellular vesicles (EVs) from probiotic bacteria.
- To compare ultracentrifugation and precipitation methods for EV isolation from Lactobacillus acidophilus and Escherichia coli Nissle.
- To characterize and quantify isolated EVs using nanoparticle-tracking analysis and Western blot.
Main Methods:
- Compared ultracentrifugation and precipitation for EV isolation from Lactobacillus acidophilus (LA) and Escherichia coli Nissle (EcN).
- Quantified EV yield and characterized EVs using nanoparticle-tracking analysis (NTA).
- Confirmed EV surface biomarkers via Western blot analysis.
Main Results:
- Ultracentrifugation yielded approximately 1.5-fold higher EV yield compared to precipitation for both LA and EcN.
- Escherichia coli Nissle (EcN) released a higher level of EVs than Lactobacillus acidophilus (LA).
- A standardized step-by-step protocol for EV isolation and characterization was established.
Conclusions:
- Ultracentrifugation is a more effective method for isolating EVs from probiotic bacteria compared to precipitation.
- The developed protocol provides a standardized approach for EV isolation from Gram-positive and Gram-negative probiotics.
- Standardized EV isolation is crucial for reliable pre-clinical studies investigating probiotic-derived EVs.
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