Unit-length irregularities in Leucine Rich Repeat structures. (a) The structure of the Ribonuclease Inhibitor (1DFJ-I) shows only minimal irregularity. The irregularity profile indicates variations in unit length λ
(blue curve) and absolute deviation | λ – λ
| from the mean unit length λ for each solenoid unit j (green curve). The two structural motifs at the bottom represent the two main structural solenoid unit motifs detected for 1DFJ. Possible positions of these structural motifs are indicated above the respective structure. (b) The LRR domain in CARMIL (A) resembles an unusually irregular Ribonuclease Inhibitor structure for which variations in the irregularity profile indicate variability in solenoid units. The structural segment of units 6 – 9 (dashed box) depicts irregularities in units in more detail. Each unit is colored according to the irregularity distribution in Figure 7. Gray segments were classified as insertions by ConSole and do not contribute to the irregularity calculation. (c) The structure of TLR4 (2Z64-A) has a distinctively more irregular region (units 5 – 10, dashed box) when compared to other segments of the structure. Irregularity in this region accrues a significant change in the curvature.