THERMODYNAMIC STABILITY OF GLOBULAR-PROTEINS - A RELIABLE MODEL FROM SMALL-MOLECULE STUDIES

In this Report the thermal denaturation of globular proteins is decomp osed in two subprocesses: i) fusion of the protein interior; ii) inter action of previously buried residues with water. The thermodynamics of the two subprocesses are estimated from experimental data on model pe ptide compounds. The protein stability curves calculated with this mod el are. reliable in comparison with experimental ones. Moreover, our d ecomposition of the denaturation Gibbs energy clarifies the physical o rigin of the so-called cold denaturation and the possible routes of th e adaptation of thermophilic proteins at temperatures above the boilin g point of water.