AN ALTERNATIVE APPROACH IN THE STRUCTURE-BASED PREDICTIONS OF THE THERMODYNAMICS OF PROTEIN UNFOLDING

A new approach for a first-order prediction of the thermodynamic prope rties of small globular proteins has been developed. The method put fo rward here has been shown to be successful in predicting, within accep table margins of uncertainty, the denaturational heat capacity changes of a given protein if its amino acid composition is known. If compare d with other models this method has the following advantages: (1) no d etails about the three-dimensional structure of the protein are requir ed; (2) comparison with the thermodynamic properties of small model co mpounds is not necessary; (3) the temperature dependence of the denatu rational heat capacity change is taken into account. Moreover, the equ ations developed have allowed us to point out the errors that can be m ade if the temperature-dependence of the denaturational heat capacity change is not taken into account in the calculation of the unfolding t hermodynamic functions. (C) 1997 Elsevier Science B.V.