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Updated: Aug 31, 2025
10:37
Comparing the Affinity of GTPase-binding Proteins using Competition Assays
Published on: October 8, 2015
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Competition in drug binding and … the race to equilibrium
Georges Vauquelin1, Dominique Maes2
1Department of Molecular and Biochemical Pharmacology, Vrije Universiteit Brussel, Brussels, Belgium.
Fundamental & Clinical Pharmacology
|August 18, 2022
Summary
Binding kinetics can be better understood using binding fluxes instead of rate constants. This novel approach offers visual insights into complex drug-target interactions and pathways.
Area of Science:
- Pharmacology
- Biophysics
- Computational Chemistry
Background:
- Binding kinetics is crucial for understanding drug selectivity and duration.
- Current descriptions of complex binding mechanisms often rely on complex algebraic equations.
- A decade ago, a shift towards binding fluxes over rate constants was proposed.
Purpose of the Study:
- To explore novel binding flux-based approaches for analyzing complex binding mechanisms.
- To provide visual insights into ligand competition and pathway selection.
- To investigate binding kinetics under non-equilibrium conditions.
Main Methods:
- Utilized differential equation-based simulations.
- Analyzed binding fluxes representing the velocity of species conversion.
- Examined competition between two ligands for a single target.
- Investigated induced fit versus conformational selection pathways within a thermodynamic cycle.
Main Results:
- Ligand-binding steps proceed at individual paces towards equilibrium.
- Competition assays may exhibit transient overshoots in bound species.
- Overshoots in thermodynamic cycles might initially suggest dominant induced fit pathways, but findings indicate otherwise under certain conditions.
- Binding flux approaches offer visual insights into complex mechanisms.
Conclusions:
- Binding flux-based approaches provide a more intuitive understanding of complex binding kinetics.
- These methods offer valuable visual insights into non-equilibrium binding events.
- The study highlights the utility of binding fluxes for analyzing drug-target interactions and molecular recognition processes.
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