Table 1.
Statistics of Data Collection and Refinement
| Data Collection | Se-SAD | Native |
|---|---|---|
| Diffraction beam | BSRF | BL38B1, Spring-8 |
| Space group | P21212 | P21212 |
| Unit cell (Å) | 88.48, 158.65, 54.94 | 86.89, 154.7, 53.54 |
| Number of molecules in ASU | 2 | 2 |
| Wavelength (Å) | 0.979 | 1.000 |
| Resolution (Å) | 30 – 3.2 (3.31 – 3.2) | 40 – 2.75 (2.85 – 2.75) |
| Rsym (%) | 11.2 (69) | 4.1 (40.8) |
| I/σ | 20.85 (2.69) | 27.95 (1.54) |
| Completeness (%) | 99.3 (100) | 95.8 (66.0) |
| Number of measured reflections | 90,304 | 60,512 |
| Number of unique reflections | 12,927 | 17,756 |
| Redundancy | 7.0 (7.3) | 3.4 (1.7) |
| Wilson B factor (Å2) | 204.6 | 111.1 |
| SAD Phasing | ||
| Anomalous scatterers | 10 Se + 2 Zn2+ | 2 Zn2+ |
| Figure of merit (FOM) | 0.391 | 0.217 |
| FOM after DM | 0.689 | 0.747 |
| FOM after phase combination | 0.789 | |
| Refinement | ||
| R factor | 0.2195 | |
| Rfree | 0.2713 | |
| No. atoms | 3516 protein atoms + 2 Zn2+ + 1 SO42− | |
| B factors | ||
| Overall | 110.33 | |
| Main chain | 107.32 | |
| Side chain | 113.11 | |
| Rmsd bond lengths (Å) | 0.011 | |
| Rmsd bond angles (°) | 1.523 | |
| Ramachandran favored (%) | 87.8 | |
| Ramachandran outliers (%) | 3.59 | |
Values in parentheses are for the highest-resolution shell. Rsym=ΣhΣi|Ih,I –Ih|/ΣhΣiIh,i, wherein Ih is the mean intensity of the i observations of symmetry-related reflections of h. R=Σ|Fobs – Fcalc|/ΣFobs, wherein Fcalc is the calculated protein structure factor from the atomic model. (Rfree was calculated with 5% of the reflections.)