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Updated: Jul 10, 2026
03:29
Synthesis and Assay of Vibrio Quorum Sensing Inhibitors
Published on: May 31, 2024
Localized quorum sensing in Vibrio fischeri
Mary E Parent1, Charles E Snyder, Nathaniel D Kopp
1Department of Chemical Engineering, The Pennsylvania State University, University Park, PA 16802, United States.
Colloids and Surfaces. B, Biointerfaces
|November 17, 2007
Summary
We studied bacterial quorum sensing in 2D, finding it depends on local cell density and signal diffusion time, not just overall population size.
Area of Science:
- Microbiology
- Bacterial Communication
- Systems Biology
Background:
- Quorum sensing is typically viewed as a population density-dependent phenomenon in 3D bacterial cultures.
- Studying quorum sensing in 3D samples makes it difficult to isolate time and distance effects on signal diffusion.
- Vibrio fischeri is a model organism for studying quorum sensing due to its bioluminescence.
Purpose of the Study:
- To investigate the role of local population density in bacterial quorum sensing.
- To examine quorum sensing in two-dimensional (2D) bacterial populations adhered to surfaces.
- To analyze quorum sensing in terms of signal diffusion dynamics.
Main Methods:
- Culturing Vibrio fischeri in 2D surface-adhered samples on glass.
- Measuring bacterial luminescent response as an indicator of quorum sensing.
- Utilizing a diffusion model to guide experiments and analyze signal propagation.
Main Results:
- Quorum sensing was observed to occur locally within 2D bacterial populations.
- The occurrence of quorum sensing is dependent on both local cell density and signal diffusion time.
- A "true quorum" threshold, defined by cell number, was identified for specific densities and diffusion times.
Conclusions:
- Bacterial quorum sensing can be a local phenomenon influenced by spatial arrangements and diffusion.
- Two-dimensional bacterial surface cultures provide a novel platform for studying quorum sensing dynamics.
- Signal diffusion and local cell density are critical factors in initiating quorum sensing.
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