UNRES model of polypeptide chains. Blue spheres
represent the peptide
groups (p), spheroids represent the side chains (SC), and small white
spheres represent the α-carbon atoms (which are not interaction
sites but only serve to assist in chain-geometry definition). The
backbone-virtual-bond angle θi,
backbone-virtual-bond-dihedral angle γi, and the two angles αi and
βi that define the location of the ith side-chain center with respect to the backbone are shown.
Reproduced from Zaborowski et al., J. Chem. Inf. Model.2015, 55, 2050 (DOI: 10.1021/acs.jcim.5b00395). Copyright 2015 American Chemical Society.