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Updated: Mar 1, 2026
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Direct Stochastic Optical Reconstruction Microscopy of Extracellular Vesicles in Three Dimensions
Published on: August 26, 2021
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Extracellular membrane vesicles harbouring viral genomes.
Marie Gaudin1, Mart Krupovic, Evelyne Marguet
1CNRS UMR 8621, Institut de Génétique et Microbiologie, Univ Paris-Sud, 91405, Orsay cedex, France.
Environmental Microbiology
|September 17, 2013
Summary
Extracellular membrane vesicles (MVs) from Thermococcus nautilus selectively package plasmid DNA, including a viral genome. These MVs facilitate intercellular transport of genetic material, suggesting a role in horizontal gene transfer.
Area of Science:
- Microbiology
- Archaea Biology
- Virology
Background:
- Extracellular membrane vesicles (MVs) are produced by cells across all three domains of life, indicating a fundamental cellular process.
- Previous research demonstrated that MVs from Thermococcus kodakaraensis can transfer exogenous plasmid DNA between cells.
Purpose of the Study:
- To investigate MV production in Thermococcus nautilus and their cargo.
- To determine if MVs from T. nautilus can package and transfer plasmid DNA, including viral genomes.
Main Methods:
- Culturing of Thermococcus nautilus.
- Isolation and characterization of extracellular membrane vesicles (MVs).
- Analysis of plasmid DNA content within MVs using molecular techniques.
Main Results:
- Thermococcus nautilus produces MVs that selectively incorporate plasmids pTN1 and pTN3.
- Plasmid pTN3 represents a defective viral genome with proteins common to viruses across all domains of life.
- MV protein composition is similar to classical MVs, lacking the viral major capsid protein.
Conclusions:
- MVs can act as vehicles for intercellular transfer of viral genomes.
- This process may facilitate genetic recombination between viral, plasmid, and cellular chromosomes without requiring viral infection.
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