Fluxes for Unraveling Complex Binding Mechanisms

Area of Science:

• Biochemistry
• Pharmacology
• Chemical Biology

Background:

• Historically, high-affinity drug binding was attributed primarily to the induced-fit pathway.
• Recent binding flux-based approaches suggest induced-fit and conformational selection pathways operate in parallel.
• The relative contribution of these pathways is concentration-dependent, particularly under equilibrium conditions.

Purpose of the Study:

• To highlight the importance of extending binding flux-based approaches to physiological nonequilibrium conditions.
• To demonstrate the application of these methods in understanding ligand-target complex formation in vivo.
• To analyze transient experimental data within a conventional thermodynamic cycle framework.

Main Methods:

• Utilizing binding flux-based approaches to analyze drug-target interactions.
• Investigating ligand-target complex formation under both equilibrium and nonequilibrium conditions.
• Applying thermodynamic cycle analysis to experimental data.

Main Results:

• Both induced-fit and conformational selection pathways contribute to high-affinity drug binding.
• The balance between these pathways is modulated by ligand concentration.
• Flux-based approaches reveal dynamic binding processes relevant to physiological conditions.

Conclusions:

• Binding flux methods offer valuable insights into drug-target interactions beyond equilibrium binding.
• Understanding parallel binding pathways is crucial for comprehending drug efficacy in vivo.
• Transient binding events can be effectively analyzed using thermodynamic cycle principles.