Table 2. Cryo-electron microscopy (cryo-EM) data collection, refinement, and validation statistics.
| M4R-Gi1-Ipx | M4R-Gi1-Ipx-LY298 | M4R-Gi1-Ipx-VU154 | M4R-Gi1-ACh | |
|---|---|---|---|---|
| Data collection & refinement | ||||
| EMD code | 26,099 | 26,100 | 26,101 | 26,102 |
| Micrographs | 5056 | 5121 | 6021 | 5913 |
| Electron dose (e-/A2) | 66 | 66 | 59.5 | 53.6 |
| Voltage (kV) | 300 | 300 | 300 | 300 |
| Pixel size (Å) | 0.83 | 0.83 | 0.83 | 0.83 |
| Spot size | ||||
| Exposure time | 4 | 4 | 3 | 5 |
| Movie frames | 76 | 76 | 75 | 71 |
| K3 CDS mode | No | No | No | Yes |
| Defocus range (µm) | 0.5–1.5 | 0.5–1.5 | 0.5–1.5 | 0.5–1.5 |
| Symmetry imposed | C1 | C1 | C1 | C1 |
| Particles (final map) | 415,743 | 617,793 | 677,392 | 315,595 |
| Resolution @0.143 FSC (Å) | 2.8 | 2.4 | 2.5 | 2.8 |
| Refinement | ||||
| CCmap–model | 0.87 | 0.87 | 0.88 | 0.82 |
| Map sharpening B factor (Å2) | –80.9 | –60.8 | –46.6 | –85.1 |
| Model quality | ||||
| PDB code | 7TRK | 7TRP | 7TRQ | 7TRS |
| R.M.S. deviations | ||||
| Bond length (Å) | 0.004 | 0.004 | 0.005 | 0.006 |
| Bond angles (o) | 0.849 | 0.811 | 0.826 | 0.773 |
| Ramachandran | ||||
| Favored (%) | 98.38 | 99.14 | 98.02 | 98.10 |
| Outliers (%) | 0 | 0 | 0 | 0 |
| Rotamer outliers (%) | 0.11 | 0.21 | 0 | 0 |
| C-beta deviations (%) | 0 | 0 | 0 | 0 |
| Clashscore | 2.69 | 2.62 | 2.26 | 4.08 |
| MolProbity score | 1.06 | 1.05 | 1.00 | 1.19 |
mAChR: muscarinic acetylcholine receptor; ACh: acetylcholine; Ipx: iperoxo; FSC: Fourier shell correlation.