Figure 6.

Comparison of cross-angle distribution of all neighboring helix pairs with the reference distribution based on their respective mismatches. (a) Distribution of all neighboring pairs (blue, with 0.9 confidence intervals as error bars) compared to the overall reference distribution (pink; see text). (b) Difference in log of probabilities between the two sets. Equivalent to the difference in estimated free energies. The plot shows higher tendency for small cross angles (−10° ≤ Ω ≤ 30°) than expected by the reference distributions and lower than expected tendency for larger cross angles absolute values (−25° < Ω < −15°), (37° < Ω < 47°), and (58° < Ω < 65°). Error bars represent 0.9 confidence intervals obtained by a 500-resample bootstrap (50) on the values of experimental cross angles. Data are omitted for |Ω| > 75° due to large uncertainty.