Related Experiment Video
Updated: May 11, 2026
03:29
Synthesis and Assay of Vibrio Quorum Sensing Inhibitors
Published on: May 31, 2024
Electronic implementation of a repressilator with quorum sensing feedback.
Edward H Hellen1, Syamal K Dana, Boris Zhurov
1Department of Physics & Astronomy, University of North Carolina Greensboro, Greensboro, North Carolina, United States of America. ehhellen@uncg.edu
Plos One
|May 10, 2013
Summary
We explored a synthetic genetic repressilator with quorum sensing feedback, revealing complex dynamics like multi-stability and period-doubling. An electronic analog confirmed these findings, showing noise amplification near bifurcations.
Area of Science:
- Synthetic biology
- Systems biology
- Nonlinear dynamics
Background:
- Genetic ring oscillators are fundamental biological circuits.
- Quorum sensing (QS) regulates bacterial communication and behavior.
- Integrating QS feedback into repressilators introduces complex regulatory interactions.
Purpose of the Study:
- To investigate the dynamical behaviors of a synthetic genetic repressilator model incorporating quorum sensing feedback.
- To explore the impact of competing inhibitory and stimulatory activities on gene expression dynamics.
- To experimentally validate computational predictions using an electronic analog circuit.
Main Methods:
- Numerical simulations of the synthetic genetic repressilator model with QS feedback.
- Design and construction of an electronic analog circuit mimicking the repressilator system.
- Experimental validation of simulated dynamical features, including multi-stability and bifurcations.
Main Results:
- Observed multi-stability of limit cycles and stable steady-states.
- Identified period-doubling, reverse period-doubling, and infinite period bifurcations.
- Reproduced simulated dynamics in the electronic analog, including noise amplification near bifurcations.
Conclusions:
- The synthetic genetic repressilator with QS feedback exhibits rich and complex nonlinear dynamics.
- Electronic analog models are effective tools for studying and validating synthetic gene circuit behaviors.
- System parameters are accessible and controllable in the designed electronic analog, facilitating further research.
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