Computational Analysis of Protein Interactions

Professor Ilya A. Vakser, Department of Cell and Molecular Pharmacology,
Medical University of South Carolina

Abstract:

The Global Range Molecular Matching (GRAMM) methodology is an empirical approach to smoothing the
macromolecular energy function by changing the range of the atom-atom potentials. The technique allows to
locate the area of the global minimum of intermolecular energy for structures of different accuracy. To predict
the structure of a complex, it requires only the atomic coordinates of the two molecules (no information about
the binding sites is needed). The procedure performs an exhaustive 6-dimensional search through the relative
translations and rotations of the molecules. The molecular pairs may be: two proteins, a protein and a smaller compound,
two transmembrane helices, etc. GRAMM may be used for high-resolution molecules (high-resolution docking), for
inaccurate structures, where only the gross structural features are known, and in cases of large conformational changes
(low-resolution docking). The high-resolution docking is designed for accurate complex predictions, in case of small
structural inaccuracies. The low-resolution docking is designed for the prediction of the gross features of a complex,
in case of major structural inaccuracies. It may also be used, for the accurate structures, to overcome the multiminima
problem, or to reveal the role of large-scale structural factors in the formation of protein complexes.