Role of Adsorbed Water in the Dynamics of Metmyoglobin

Abstract
By microwave measurements we have determined the dielectric relaxation rate for adsorbed water in metmyoglobin crystals in the temperature range from 100 to 300 K. The temperature dependence of the dielectric relaxation rate of the adsorbed water is nearly identical to the temperature dependence of the conformational fluctuation rate of the protein as measured by the Mössbauer effect. This surprising correlation may be understood in terms of the mechanical and electrical interactions between the adsorbed water and the protein.