Freezing of Dynamics of a Methyl Group in a Protein Hydrophobic Core at Cryogenic Temperatures by Deuteron NMR Spectroscopy

摘要

Proteins undergo a number of significant changes when their temperature is dropped from the physiological range to much lower values. A so-called glass transition, occurring at ～200-230 K, is one of the most studied dynamical changes undergone by proteins in a solid state. This dynamic transition leads to a loss of biological activity as a result of freezing of slow collective modes of motions, as evidenced from X-ray diffraction, neutron scattering studies, dielectric spectroscopy, and NMR relaxation measurements.