Influence of kinetic barriers on the structures of non-covalently bonded states

Abstract

The dissociation of two similar bimolecular complexes, of comparable thermodynamic stabilities, but different kinetic stabilities, is considered. Relative to the complex with the lower kinetic barrier to dissociation, it is concluded from proton NMR data that the complex with the higher kinetic barrier to dissociation has, at a defined point, a tighter interface and a less dynamic structure. The work illustrates how high kinetic barriers to dissociation of non-covalently bonded states can improve bonding at parts of the non-covalently bonded interface. The conclusions drawn should be of general relevance to the non-covalent complexes that are involved in biological functions.