Comparison of the evolution of the unit twist angles (°) along the α-helix, from turns (i-11, i-8) to (i+4, i+7), between a Pro-containing polyAla α-helix (control, solid black line) and (a) (S/T)P, (b) (S/T)AP, (c) (S/T)AAP, (d) P(S/T), (e) PA(S/T), and (f) PAA(S/T) motifs. The color and style codes are: Ser (red), Thr (blue), g+ rotamer (solid line), g− rotamer interacting with the carbonyl oxygen at position j-4 (dotted line), and g− rotamer interacting with the carbonyl oxygen at position j-3 (dashed line).