"Iso-depth contour map" of a molecular surface.

The representation and display of protein surfaces are useful in many areas of molecular modeling, and surface shape study is particularly important in the analysis of protein-ligand interactions. We introduce here the notion of the molecular surface convex hull, allowing the depth of any molecular surface point to be defined. A two-dimensional (2D) map, the iso-depth contour map, and a three-dimensional (3D) representation, the iso-depth lines, allow the topography of a molecular surface to be displayed in terms of knobs (high depth) and holes (low depth).