Table 1.
Cryo-EM data collection, refinement, and validation statistics
| Singly loaded UBA6-BIRC6UBC-UbT complex (EMD- 66842, PDB 9XGB) | Doubly loaded UBA6-BIRC6UBC-UbT-UbA complex (EMD- 66843, PDB 9XGC) | |
|---|---|---|
| Magnification | 96000 | 96000 |
| Voltage (kV) | 300 | 300 |
| Spherical aberration (mm) | 2.7 | 2.7 |
| Detector | Falcon4 | Falcon4 |
| Electron exposure (e-/Å2) | 51.35 e–, 32 frames | 51.35 e–, 32 frames |
| Defocus range (μm) | -1.5 to -2.0 | -1.5 to -2.0 |
| Pixel size (Å) | 0.808 | 0.808 |
| Symmetry imposed | C1 | C1 |
| Box size (pixel) | 200 | 200 |
| Micrographs (no.) | 21555 | 21555 |
| Initial particle images (no.) | 14,438,711 | 14,438,711 |
| Final particle images (no.) | 1,201,224 | 1,087,360 |
| Map resolution (Å) | 3.3 Å | 3.4 Å |
| Map resolution range | 2.9-5.8 Å | 2.9-5.8 Å |
| FSC threshold | 0.143 | 0.143 |
| Initial model use (PDB code) | 1UBQ, 3CEG, 7PVN | 1UBQ, 3CEG, 7PVN |
| Model resolution (Å) | 4.0 Å | 3.5 Å |
| FSC threshold | 0.5 | 0.5 |
| Map sharpening B factor (Å2) | -180 | -180 |
| Nonhydrogen atoms | 10826 | 11421 |
| Protein residues | 1366 | 1440 |
| Nucleotides | 0 | 0 |
| Protein | 30.00/534.77/209.50 | 131.16/461.09/237.04 |
| Nucleotide | --- | --- |
| Bond lengths (Å) | 0.009 | 0.008 |
| Bond angles (°) | 1.428 | 1.143 |
| MolProbity score | 1.66 | 1.71 |
| Clashscore | 6.76 | 7.76 |
| Poor rotamers (%) | 1 | 0.08 |
| Favored (%) | 95.88 | 95.86 |
| Allowed (%) | 4.05 | 4.14 |
| Disallowed (%) | 0.07 | 0 |