Figure 2.

Scatterplot of τ₁₀₁ vs. α₁₀₁ for the antibody set. The gray, shaded regions represent ± 3.0 σ from the mean of the distribution presumed to represent the kinked subpopulation. Each point is colored by number of stabilizing hydrogen bonds in the structure. Although α₁₀₁ is useful for isolating structures with these hydrogen bonds, there is a small subpopulation of well-hydrogen bonded structures with high values of τ₁₀₁ (~140°), suggesting that neither τ₁₀₁ nor α₁₀₁ alone suffices to describe the kinked conformation. Structures in this region possess a β-bulge at position 101 but resume β-sheet strands C-terminal from the bulge.