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Updated: Jun 14, 2026

Incorporating Target Protein Structure Flexibility and Dynamics in Computational Drug Discovery Using Ensemble-Based Docking Analysis
Published on: June 20, 2025
Computational study of small molecule binding for both tethered and free conditions
1Department of Physics, University of Idaho, Moscow, Idaho 83844-0903, USA. ytreberg@uidaho.edu
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Using a calix[4]arene-benzene complex as a test system, we compare the potential of mean force for when the calix[4]arene is tethered versus free. When the complex is in vacuum, our results show that the difference between tethered and free is primarily due to the entropic contribution to the potential of mean force resulting in a significant binding free energy difference of 6.6 kJ/mol. By contrast, when the complex is in water, our results suggest that there is no appreciable difference between tethered and free. This study elucidates the roles of entropy and enthalpy for this small molecule system and emphasizes the point that tethering the receptor has the potential to dramatically impact the binding properties. These findings should be taken into consideration when using calixarene molecules in nanosensor design.
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