Table 2. Image processing report.
| Parameter | Data set 1 | Data set 2 |
|---|---|---|
| Micrographs | ||
| Camera | K2, superresolution | K2, superresolution |
| Magnification | 48077 | 48077 |
| Number | 218 | 1136 |
| Tilt (°) | 0 | 30 |
| Frames per micrograph | 54 | 50 |
| Frame rate (/s) | 4 | 4 |
| Dose per frame (e−/pixel) | 1.08a | 0.76a |
| Accumulated dose (e−/Å2) | 51 | 33 |
| Frame alignment | bseries | bseries |
| CTF | ||
| Defocus range (µm) | 1.04–2.92 | 1.06–3.23 |
| Correction | Phase flip | Phase flip |
| Particles | ||
| Picked | 39536 | 26702 |
| Used in final 2D averages/3D reconstruction | 19701 (50%) | 18646 (70%) |
| Alignment | ||
| Initial reference map | PBD: 3JD6 | PBD: 3JD6 |
| Low-pass filter limit (Å) | 35 | 20 |
| Projection-matching algorithm | Cross-correlation | Cross-correlation |
| Number of iterations | 5 | 4 |
| Reconstruction | ||
| Classes | 70 | 1 |
| Size | 330 × 330 × 1 | 224 × 224 × 224 |
| Pixel size (Å) | 1.04 | 1.04 |
| Symmetry | C1 | C2 |
| Resolution limit (Å) | 2.1 | 3.0 |
| Resolution estimate (Å, FSC0.143) | 5–25 | 10.0 |
| Masked | No | Yes |
| Sharpened | No | Yesb |
| Filtered | No | Low-pass to 10 Å |
a
The micrographs were taken in superresolution mode and subsequently binned for further processing (final size: 3838 × 3710).
b
Amplitudes weighted to match PDB accession no. 3JD6.