Related Experiment Video
Updated: Jun 4, 2026
07:26
Size Exclusion Chromatography to Analyze Bacterial Outer Membrane Vesicle Heterogeneity
Published on: March 31, 2021
Symbiotic bacteria produce non-lytic vesicles with nucleic acid cargo
Nurila Kambar1, Yulin Song2, Carmen M Herrera3
1Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA.
Nature Communications
|June 2, 2026
Summary
Honeybee gut symbionts release membrane vesicles containing nucleic acids (NAs), potentially mediating molecular communication. This discovery offers new avenues for enhancing bee immunity and delivering therapeutics.
Area of Science:
- Microbiology
- Symbiotic interactions
- Molecular biology
Background:
- Gut symbionts significantly impact host physiology, but molecular signal exchange mechanisms are unclear.
- Membrane vesicles (MVs) are proposed mediators of cytoplasmic content exchange, including nucleic acids (NAs).
- Previous studies on bacterial MVs have faced challenges due to imprecise reporting of vesicle type and composition.
Purpose of the Study:
- To investigate the production and cargo of membrane vesicles (MVs) from honeybee gut symbionts.
- To differentiate between lytic and non-lytic MV production in Gram-negative bacteria.
- To determine the NA content and origin within MVs from symbiotic bacteria.
Main Methods:
- Utilized cryogenic electron microscopy (cryo-EM) to analyze MV ultrastructure and differentiate vesicle types (OMVs, OIMVs).
- Developed a method to distinguish between lytic and non-lytic bacterial membrane vesicle release.
- Performed DNA and RNA content assays on MVs from various bacterial strains, including honeybee symbionts and non-symbionts.
Main Results:
- Honeybee gut symbionts (Snodgrassella alvi, Gilliamella apicola, Gilliamella apis) produce non-lytic MVs enriched in NAs.
- Distinguished outer membrane vesicles (OMVs) and outer-inner membrane vesicles (OIMVs) from membrane debris and self-assembled vesicles.
- Symbiotic MVs contained significantly higher NA levels compared to non-symbiotic MVs, with confirmed cytoplasmic origin in S. alvi.
Conclusions:
- Symbiotic bacteria utilize non-lytic MVs for NA export, potentially facilitating intercellular communication.
- The findings provide a mechanism for RNAi activity observed in engineered S. alvi.
- This research opens possibilities for engineering gut symbionts for honeybee health and NA-based therapeutic delivery.
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