Solvent Effects in Carbohydrate Binding by Synthetic Receptors: Implications for the Role of Water in Natural Carbohydrate Recognition

摘要

Carbohydrate recognition is a key natural phenomenon that mediates protein trafficking and function, cell-cell recognition and adhesion, and many aspects of the immune response. Despite its importance, it is not well understood in all respects. In particular, the driving force for saccharide binding by lectins and other carbohydrate-binding proteins is subject to debated The discussion centers on the part played by water. Crystal structures of protein-carbohydrate complexes reveal dense networks of intermolecular hydrogen bonds, but these bonds can only form after desolvation of the binding surfaces. Complex formation [Eq.(1)] involves the interchange of carbohydrate-OH groups with H2O molecules, which is not an obviously favorable process.