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Published on: May 10, 2020
Second-chance signal transduction explains cooperative flagellar switching
Henry G Zot1, Javier E Hasbun, Nguyen Van Minh
1Department of Biology, University of West Georgia, Carrollton, Georgia, United States of America. hzot@westga.edu
Plos One
|July 31, 2012
Summary
This study presents a new model for flagellar motor switching, explaining cooperative responses without allosteric interactions. It reveals energy coupling between switch and motor units, driven by steady-state and regulated by ligand binding.
Area of Science:
- Microbiology
- Biophysics
- Systems Biology
Background:
- Flagellar motion reversal (switching) involves interactions between rotor switch complexes and stator motor units.
- Existing models for cooperative ligand-induced switching often propose allosteric interactions within the rotor.
Purpose of the Study:
- To derive an analytical expression for energy coupling between flagellar switch and motor units.
- To demonstrate a model that explains cooperative switching without invoking allosteric interactions.
Main Methods:
- Analytical derivation of energy coupling between switch and motor units.
- Computational simulation to reproduce analytical results based on specific conditions.
Main Results:
- A novel model accounts for cooperative switching response without requiring allosteric interactions.
- Energy coupling is driven by steady-state and regulated by stochastic ligand binding.
- The derived analytical function is a generalized form of the Hill equation.
Conclusions:
- The proposed model offers a new perspective on flagellar motor switching mechanisms.
- It highlights the role of energy coupling and stochastic ligand binding in signal transduction.
- This framework provides a mathematically defined mechanism for flagellar motor regulation.
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