Conformational Proofreading: The Impact of Conformational Changes on the Specificity of Molecular Recognition

Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot, Israel.
PLoS ONE (Impact Factor: 3.23). 02/2007; 2(5):e468. DOI: 10.1371/journal.pone.0000468
Source: PubMed


To perform recognition, molecules must locate and specifically bind their targets within a noisy biochemical environment with many look-alikes. Molecular recognition processes, especially the induced-fit mechanism, are known to involve conformational changes. This raises a basic question: Does molecular recognition gain any advantage by such conformational changes? By introducing a simple statistical-mechanics approach, we study the effect of conformation and flexibility on the quality of recognition processes. Our model relates specificity to the conformation of the participant molecules and thus suggests a possible answer: Optimal specificity is achieved when the ligand is slightly off target; that is, a conformational mismatch between the ligand and its main target improves the selectivity of the process. This indicates that deformations upon binding serve as a conformational proofreading mechanism, which may be selected for via evolution.

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Available from: Tsvi Tlusty
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