Table 1.
Restraints and Structural Statistics
| Restraints | |
| Total experimental restraints | |
| Total distance restraints | 1306 |
| Intraresidue (i = j) | 492 |
| Sequential (∣i – j∣ =1) | 361 |
| Short range (1 < ∣i – j∣ ≤ 4) | 144 |
| Long range (∣i – j∣ > 4) | 259 |
| Hydrogen bond | 50 |
| Total dihedral restraintsa | 373 |
| Phi | 217 |
| Psi | 162 |
| Chi1 | 180 |
| Total dipolar couplings | |
| HNN | 58 |
| CαHα | 51 |
| CαC’ | 41 |
| NOE violation > 0.5 Å | 0 |
| Dihedral angle violation > 5 deg. | 1 |
| SANS (D2O)b Range | 0.03-0.2577 Å-1 |
|
| |
| Rmsds | |
|
| |
| Deviation from idealized geometry | |
| Bonds (Å) | 0.0015 ± 0.0002 |
| Angles (deg.) | 0.35 ± 0.03 |
| Impropers (deg.) | 0.31 ± 0.1 |
| Backbone rmsds in regular secondary structurec (Å) | 0.3 3 ±0.05 |
| Nonhydrogen atoms in regular secondary structure (Å) | 0.85 ± 0.2 |
| Rmsds from Residual dipolar coupling | |
| NH | 0.49 ±0.03 |
| CαHα | 0.79 ±0.04 |
| C’Cα | 0.63 ±0.03 |
| χ2 (Exp. SANS vs. bkCalc SANS)d | 1.23 ± 0.14 |
|
| |
| Energies | |
| E(NOE) (kcal/mol) | 56.2 ± 3.0 |
| E(dihed.) (kcal/mol) | 9.2 ± 1.0 |
| E(repel) (kcal/mol) | 52.5 ± 7.0 |
| E(RDC) (kcal/mol) | 106.33 ± 10 |
| E(SANS) (kcal/mol) | 20.21 ± 0.5 |
a
Note: Torsion angles are restrained ambiguously due uncertainty in stereo-specific assignments and in NOE assignment.61
b
The SANS in D2O was used for the refinement.
c
Regular secondary structure elements are the α-helices 1 (residues 35–47), 2 (75–82), 3 (101–109), 4 (120–134); 310-helix (24–26); β-strands 1 (6–13), 2 (52–60), 3 (64–66), 4 (98–99) and 5 (137–139).
d
The χ2 between experimental and back-calculated SANS. The χ2 is defined in the text.