Table 3.
Summary of structure determination and refinement
| Diffraction data | |||
|---|---|---|---|
| Data set | Ligand free | Chitotriose | His8-ligand free |
| Space group | P6122 | P1 | P6122 |
| Cell constants (Å) | a, b = 112.38 c = 175.66 |
a = 47.90 b = 59.70 c = 60.20 α = 73.0° β = 90.7° γ = 76.4° |
a, b = 109.86 c = 173.097 |
| Resolution limit (Å) | 20 – 2.0 (2.0 – 2.1) | 20 – 1.9 (1.9 – 2.0) | 50 – 2.3 (2.3 – 2.4) |
| Measured Reflections | 201733 (24219) | 114167 (18462) | 416130 (50104) |
| Unique reflections | 41642 (4561) | 46020 (7188) | 27885 (3231) |
| Redundancy | 4.8 (5.3) | 2.5 (2.6) | 14.9 (15.5) |
| Mean I/σ (I) | 9.8 (8.0) | 11.0 (8.0) | 21.2 (4.4) |
| Rsym (I) | 0.112 (0.240) | 0.075 (0.164) | 0.112 (0.75) |
| Refinement statistics | |||
|---|---|---|---|
| Resolution range used for refinement (Å) |
15 – 2.0 (2.0 – 2.05) | 15 – 1.9 (1.9 – 1.95) | 46 – 2.3 (2.3 – 2.36) |
| No. reflections used | 41187 (2836) | 43261 (3210) | 26580 (1926) |
| Completeness % | 97.09 (93.37) | 93.8 (95.26) | 99.58 (99.16) |
| Rcryst | 0.242 (0.406) | 0.195 (0.198) | 0.233 (0.282) |
| No. reflection for Rfree | 2260 (150) | 2325 (170) | 1407 (83) |
| Rfree | 0.250 (0.371) | 0.254 (0.306) | 0.269 (0.375) |
| Model contents (resid.) | |||
|---|---|---|---|
| Amino acid | 326 | 636 | 325 |
| H2O | 299 | 316 | 48 |
| Carbohydrate | - | 12 | - |
| Average B factor (Å2) | 32.15 | 23.31 | 34.22 |
| Estimated coordinate error (Rfree / Å) |
0.135 | 0.181 | 0.198 |
| Rmsd from ideal bond length (Å) |
0.006 | 0.013 | 0.015 |
| Rmsd from ideal bond angle (°) |
1.4 | 2.1 | 2.1 |
| Ramachandran geometry | |||
|---|---|---|---|
| Most favoured | 86.1 % (236) | 89 % (477) | 85.7% (233) |
| Allowed | 12.8 % (35) | 10.6 % (57) | 13.6 % (37) |
| Generously allowed | 0.4 % (1) | 0.4% (2) | 0.4% (1) |
| Disallowed | 0.7 % (2) | 0 | 0.4 % (1) |
| PDB ID | 2R0F | 2R0H | - |