[The role of vitrification in maintaining protein native structure during dehydration]

Concentration dependencies of maximum temperature (Td), thermal effect of denaturation (delta Qd) and also of glass transition temperature (Tg) were obtained in heat capacity investigation of five globular proteins with low water content. Special features of the observed Td and delta Qd dependencies, both general for polymers and specific for proteins, are discussed. The assumption is put forward that anomalously strong dependence of protein Tg on humidity, bringing together glass and denaturation transitions, results in the fact that denaturation process can be observed in completely dehydrated proteins. The denaturation parameters of dry proteins were determined.