Side-chain centers provide most informative reference points for both WCN and
Voronoi tessellation. (A) Distribution of correlations of WCN with ER, for seven
different coordinate sets according to which WCN was calculated: SC, AA, CB, CA,
N, C, O. Each coordinate set represents a different way of identifying the
reference location of each residue. For SC (Side Chain) and AA (entire Amino
Acid), the reference point is given, respectively, by the geometric average
coordinates of the Side Chain (SC) atoms and the entire Amino Acid (AA) atoms.
The latter include the backbone but exclude any Hydrogen. The coordinate sets
CB, CA, N, C, and O use the respective atom in the amino acid as the reference
point. (B) As in (A), but using Voronoi Cell Volume instead of WCN. (C) As in
(A), but the correlations are calculated with RSA instead of with ER. (D) As in
(B), but the correlations are calculated with RSA instead of with ER.