Table 1.
X-ray diffraction data collection and refinement statistics
| Dimer | Trimer | |
|---|---|---|
| Data collection statistics | ||
| Resolution limit (Å) | 1.6 | 2.0 |
| Unique reflections | 73654 | 55552 |
| Redundancya | 4.70 (4.36) | 4.71 (4.56) |
| Completenessa (%) | 93.6 (69.9) | 94.9 (97.0) |
| I/σa | 28.36 (4.54) | 26.85 (4.25) |
| Rsyma,b (%) | 4.0 (29.4) | 4.6 (40.8) |
| Refinement statistics | ||
| Polypeptide chains | 2 | 3 |
| Protein atoms | 3535 | 5542 |
| Water molecules | 418 | 488 |
| MPD molecules | 4 | 0 |
| Tris molecules | 1 | 0 |
| Residues in allowed regions of Ramachandran plot (%) | 100 | 100 |
| Residues in most favored regions of Ramachandran plot (%) | 91.3 | 89 |
| RMSD bond lengths (Å) | 0.012 | 0.0078 |
| RMSD bond angles (deg) | 1.61 | 1.50 |
| Mean B value (Å2) | 32.0 | 40.1 |
| RMSD main chain B (Å2) | 2.20 | 1.52 |
| Resolution range (Å) | 45.5–1.6 | 50–2.0 |
| R-factorc | 20.3 | 22.2 |
| Free R-factorc | 22.5 | 25.2 |
| aValues for last shell given in parentheses. | ||
| bRsym=∑(I−〈I〉)/I. 〈I〉 is the average intensity over symmetry equivalent reflections. | ||
| cR-factor=(∑∣∣Fobs∣−∣Fcalc∣∣)/∑∣Fobs∣, where the summation is over the working set of reflections. For the free R-factor, the summation is over the test set of reflections (5% of the total reflections). | ||