Table 1.
Statistics of NMR restraints-guided computations of chl1 intronic quadruplex.
| A. NMR restraints | ||
|---|---|---|
| Distance restraintsa | Non-exchangeable | Exchangeable |
| Intra-residue distance restraints | 120 | 0 |
| Sequential (i, i+1) distance restraints | 55 | 5 |
| Long-range (i, ≥ i+2) distance restraints | 3 | 42 |
| Other restraints | ||
| Hydrogen bonding restraints (H-N, H-O, and heavy atoms) | 52 | |
| Torsion angle restraintsa | 49 | |
| Intensity restraints | ||
| Non-exchangeable protons (each of five mixing times) | 178 | |
| B. Structure statistics in 17 molecules following the intensity refinement | ||
|---|---|---|
| NOE violations | ||
| Number (> 0.2Å) | 0.0±0.0 | |
| r.m.s.d. of violations | 0.02±0.00 | |
| Deviations from the ideal covalent geometry | ||
| Bond lengths (Å) | 0.01±0.00 | |
| Bond angles (deg.) | 0.83±0.01 | |
| Impropers (deg) | 0.30±0.01 | |
| NMR R-factor (R 1/6) | 0.02±0.02 | |
| Pairwise all heavy atom r.m.s.d. values (17 refined structures) | ||
| All heavy atoms except T15 | 0.47±0.12 | |
| All heavy atoms | 0.64±0.15 | |
a
The residues G1, G5, G11, G16 were restrained to χ values in the 60 (±30)° range, characteristic of syn glycosidic torsion angles, identified experimentally. All other residues were restrained to χ values in the 240 (±70)° range, characteristic of anti glycosidic torsion values. The ε of the residues G1-G18 was restrained to the stereochemically allowed range 225 (±75)°. The γ torsion angle of the residues 1, 2, 4, 7, 8, 9, 17, 18, 19 was restrained to the values of 60 (±35)°, for residues 5, 10, 11 to 180 (±35)°, identified experimentally.