Fig. 3.

Side-chain-rotamers potential surfaces plotted in angles α′ and β′ (cf. Figure 1) of selected amino-acid residues: Ala (a), Pro (b), Val (c), Phe (d), Glu (e), and Arg (f) for virtual-bond-angle θ = 140°. See Figure 2 for detailed description. The data to calculate the statistical potentials were taken from residues not involved in regular secondary structures except proline for which all data were taken because of the small number of proline residues with θ ≈ 140°.