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Updated: May 31, 2026
09:42
Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
Published on: January 16, 2016
A multidisciplinary approach to probing enthalpy-entropy compensation and the interfacial mobility model
Erin M Wilfong1, Yuri Kogiso, Sivaramakrishnan Muthukrishnan
1Department of Chemistry, Duke University, Durham, North Carolina 27708, USA.
Journal of the American Chemical Society
|June 23, 2011
Summary
Interfacial mobility explains ligand binding affinity and enthalpy-entropy compensation. Raman spectroscopy, calorimetry, and crystallography reveal protein contraction correlates with this compensation, supporting the interfacial mobility model.
Area of Science:
- Biophysics
- Structural Biology
- Biochemistry
Background:
- Interfacial mobility is a key concept explaining ligand binding affinity.
- Enthalpy-entropy compensation is a common observation in biological systems.
- Previous studies linked protein contraction and reduced mobility to binding entropies, but Raman spectroscopy was not used.
Purpose of the Study:
- To investigate the relationship between protein contraction and enthalpy-entropy compensation using Raman difference spectroscopy.
- To evaluate the validity of the interfacial mobility model in explaining these phenomena.
Main Methods:
- Nonresonance Raman difference spectroscopy
- Isothermal titration calorimetry
- X-ray crystallography
Main Results:
- Protein contraction, indicated by increased interior packing and reduced residual movement, was correlated with enthalpy-entropy compensation trends.
- The findings align with predictions of the interfacial mobility model.
Conclusions:
- Raman difference spectroscopy, calorimetry, and crystallography support the interfacial mobility model.
- Protein contraction is linked to enthalpy-entropy compensation, reinforcing the model's relevance to protein activity.
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