Hydrogen-Bond Dynamics and Energetics of Biological Water

Abstract

Water molecules in the immediate vicinity of biomacromolecules and biomimetic organized assemblies often exhibit a markedly distinct behavior from that of their bulk counterparts. The overall sluggish behavior of biological water substantially affects the stability and integrity of biomolecules, as well as the successful execution of various crucial water‐mediated biochemical phenomena. In this minireview, we provide insights into the features of truncated hydrogen‐bond networks that grant biological water its unique characteristics. In particular, we present the experimental and theoretical efforts, based on chemical kinetics, that have shed light on the dynamics and energetics governing such characteristics. We emphasize how such details help frame our understanding of the energetics of biological water, an aspect relatively less explored than its dynamics. For instance, when biological water at hydrophilic or charged protein surfaces was explored, the free energy of H‐bond breakage was found to be of the order of 0.4 kcal·mol ‐1 higher than that of bulk water.