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Updated: Aug 2, 2026
11:42
Iterative Optimization of DNA Duplexes for Crystallization of SeqA-DNA Complexes
Published on: November 1, 2012
Structural and thermodynamic strategies for site-specific DNA binding proteins
L Jen-Jacobson1, L E Engler, L A Jacobson
1Department of Biological Sciences University of Pittsburgh, Pittsburgh, PA 15260, USA. ljen@pitt.edu
Structure (London, England : 1993)
|November 18, 2000
Summary
Protein-DNA binding strategies vary: undistorted DNA uses favorable enthalpy, while distorted DNA uses favorable entropy. This study reveals isothermal enthalpy-entropy compensation in these interactions.
Area of Science:
- Biochemistry
- Structural Biology
- Thermodynamics
Background:
- Site-specific protein-DNA complexes exhibit diverse structural properties and thermodynamic binding strategies.
- Understanding these principles can inform rational design of protein-DNA interactions.
Purpose of the Study:
- To analyze the relationship between DNA distortion and thermodynamic parameters in protein-DNA complexes.
- To investigate enthalpy-entropy compensation in protein-DNA associations.
Main Methods:
- Analysis of thermodynamic parameters (enthalpy and entropy changes) for ten site-specific protein-DNA complexes.
- Correlation of these parameters with the degree of DNA distortion.
Main Results:
- A direct correlation exists between DNA distortion and thermodynamic parameters.
- Complexes with undistorted DNA are driven by favorable enthalpy, while highly distorted DNA complexes are driven by favorable entropy.
- Protein-DNA associations exhibit isothermal enthalpy-entropy compensation, where enthalpy and entropy changes are not independent.
Conclusions:
- Isothermal enthalpy-entropy compensation indicates a trade-off between structural fit and entropic penalties.
- An optimal, unstrained fit incurs entropic costs from immobilization.
- A strained interface, while enthalpically weaker, results in smaller entropic penalties.
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