Entropy-Driven Protein Allosteric Effect in Cells Highlights the Role of Solvation Water Molecules

Allosteric effects are critical for protein function. The mechanisms by which allosteric effects propagate in cellular environments remain intriguing yet unresolved questions. In this study, we investigated the allosteric effects involved in a protein-protein binding process within Escherichia coli cells. Mutations far away from the binding interface were introduced, which alter the affinity through allosteric effects. The results indicate that entropy contributes favorably to the allosteric effect in cellular contexts. This entropy-driven allosteric effect is also corroborated by molecular dynamics (MD) simulations, which underscore the significance of the protein solvation water. The crowded macromolecules help to restrain solvation water, and the release of these water molecules creates a positive entropic gain, which in turn generates an allosteric effect in cells.