Double Mutant Cycles as a Tool to Address Folding, Binding, and Allostery

Area of Science:

• Biochemistry
• Structural Biology
• Biophysics

Background:

• Quantifying intramolecular and intermolecular interactions in protein structures is experimentally challenging.
• Energetic coupling describes short- and long-range interactions between protein residues.

Purpose of the Study:

• To review the double-mutant cycles analysis methodology for characterizing protein interactions.
• To highlight its application in studying allosteric mechanisms and protein folding pathways.

Main Methods:

• Detailed explanation of the thermodynamic principles and equations underlying double-mutant cycles analysis.
• Discussion of the methodology's application in protein-ligand complexes and protein systems.

Main Results:

• Demonstrates the power of double-mutant cycles in identifying and quantifying long-range interactions.
• Illustrates its utility in mapping allosteric networks and investigating elusive states in protein folding.

Conclusions:

• Double-mutant cycles analysis is a robust thermodynamic approach for dissecting complex protein interactions.
• The review provides guidance on experimental considerations and potential pitfalls for effective application.