An analytical method for computing atomic contact areas in biomolecules
Article first published online: 10 SEP 2012
Copyright © 2012 Wiley Periodicals, Inc.
Journal of Computational Chemistry
Volume 34, Issue 2, pages 105–120, 15 January 2013
How to Cite
Mach, P. and Koehl, P. (2013), An analytical method for computing atomic contact areas in biomolecules. J. Comput. Chem., 34: 105–120. doi: 10.1002/jcc.23111
- Issue published online: 3 DEC 2012
- Article first published online: 10 SEP 2012
- Manuscript Revised: 7 AUG 2012
- Manuscript Received: 20 JUN 2012
- NIH. Grant Number: GM080399
- space-filling diagrams;
- Laguerre diagrams;
- contact area;
We propose a new analytical method for detecting and computing contacts between atoms in biomolecules. It is based on the alpha shape theory and proceeds in three steps. First, we compute the weighted Delaunay triangulation of the union of spheres representing the molecule. In the second step, the Delaunay complex is filtered to derive the dual complex. Finally, contacts between spheres are collected. In this approach, two atoms i and j are defined to be in contact if their centers are connected by an edge in the dual complex. The contact areas between atom i and its neighbors are computed based on the caps formed by these neighbors on the surface of i; the total area of all these caps is partitioned according to their spherical Laguerre Voronoi diagram on the surface of i. This method is analytical and its implementation in a new program BallContact is fast and robust. We have used BallContact to study contacts in a database of 1551 high resolution protein structures. We show that with this new definition of atomic contacts, we generate realistic representations of the environments of atoms and residues within a protein. In particular, we establish the importance of nonpolar contact areas that complement the information represented by the accessible surface areas. This new method bears similarity to the tessellation methods used to quantify atomic volumes and contacts, with the advantage that it does not require the presence of explicit solvent molecules if the surface of the protein is to be considered. © 2012 Wiley Periodicals, Inc.