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Updated: Aug 6, 2025
09:36
Direct Stochastic Optical Reconstruction Microscopy of Extracellular Vesicles in Three Dimensions
Published on: August 26, 2021
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Stochastic effects in bacterial communication mediated by extracellular vesicles
Brian P Weaver1, Christoph A Haselwandter1,2, James Q Boedicker1,3
1Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089, USA.
Physical Review. E
|March 18, 2023
Summary
Bacterial communication using quorum sensing (QS) is enhanced by extracellular vesicles, which amplify signal fluctuations and enable long-distance communication between colonies, even with signal degradation.
Area of Science:
- Microbiology
- Systems Biology
- Biophysics
Background:
- Quorum sensing (QS) enables bacteria to coordinate multicellular behaviors based on cell density.
- Traditionally, QS relied on freely diffusing signal molecules, but extracellular vesicles (EVs) are increasingly recognized for signal transport.
- The impact of EV-mediated signal delivery on bacterial communication dynamics remains poorly understood.
Purpose of the Study:
- To investigate how packaging signal molecules in EVs affects bacterial communication.
- To model the exchange of both free and vesicle-associated QS signal molecules.
- To determine the role of EVs in signal amplification and inter-colony communication.
Main Methods:
- Developed a stochastic reaction-diffusion model for QS.
- Incorporated both freely diffusing and vesicle-associated signal molecules into the model.
- Simulated bacterial communication dynamics under varying conditions.
Main Results:
- EV-mediated signal delivery amplifies local signal concentration fluctuations.
- This amplification significantly impacts the dynamics and spatial range of bacterial communication.
- EVs provide an alternative pathway for signal transport between bacterial colonies.
Conclusions:
- Extracellular vesicles play a crucial role in bacterial communication by modulating signal dynamics.
- Vesicle-mediated QS is vital for coordinating multicellular behaviors and long-distance signaling.
- This mechanism is particularly important in environments with high degradation rates of free signal molecules.
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