Prediction of the structure of proteins using related structures,energy minimization and computer graphics

Insight into the functions and interactions of proteins may be gained by correlating a variety of types of experimental data (including kinetics, spectroscopy, biophysical measurements, among others) with three-dimensional structural models displayed and manipulated using interactive computer graphics. Although tertiary structures have been determined for a large number of proteins, one limiting factor in structure-function studies is the lack of availability of the structural coordinates of specific proteins for which other types of detailed experimental data are known. However, as the data base of known structures grows, it becomes more and more likely that the structure of a closely related protein will be available. Here we present a method for predicting structures by ( 1 ) careful alteration of a known structure of a homologous, functionally analogous protein followed by (2) energy minimization to optimize the predicted structure. This method provides a rapid and effective solution to the initial problem of obtaining a working structure for modeling studies.