Statistical Geometry and Topology of Real and Model Protein Structures

We have subjected several sets of real and simplified model proteins to Delaunay tessellation and have computed statistics on both Delaunay simplex geometry and the tendency of quadruplets of residue types to be joined together in simplices. We have characterized the geometry and contact patterns of real proteins and some of the ways in which they differ from these model structures. We have also found heretofore unreported asymmetries in contact patterns among residue quadruplets joined in simplices in real proteins.