Table 1.
Cryo-EM structure determination and model statistics for SpRecA-ssDNA and SpRecA-dsDNA complexes
| Data collection | SpRecA–ssDNA complex | SpRecA–dsDNA complex |
|---|---|---|
| Magnification | X190 000 | X120 000 |
| Defocus range (μm) | –0.8 to –2.5 | –0.8 to –2.5 |
| Voltage (kV) | 200 | 200 |
| Microscope | Talos | Talos |
| Camera | Falcon 3 | Falcon 3 |
| Frame exposure time (s) | 0.8 | 1 |
| # movie frames | 40 | 20 |
| Total electron dose (e−/Å−2) | 36 | 60 |
| Pixel size (Å) | 0.76 | 1.24 |
| Reconstruction | RecA–ssDNA complex | RecA–dsDNA complex |
| Boxe size (pixel) | 180 | 180 |
| Inter-box distance (Å) | 100 | 100 |
| # segments extracted | 363 828 | 1 109 194 |
| # segements after Class2D | 188 475 | 715 954 |
| Resolution (Å) | 3.9 | 3.8 |
| Map sharpening B-factor (Å-2) | –141.9 | –153.07 |
| Helical rise (Å) | 15.38 | 14.97 |
| Helical twist (°) | 58.46 | 58.62 |
| Atomic model | RecA–ssDNA complex | RecA–dsDNA complex |
| Chains | 9 | 10 |
| # unique non-hydrogen atoms | 10 381 | 10 515 |
| R.m.s.d. Length (Å) | 0.006 | 0.007 |
| R.m.s.d. Angles (°) | 0.993 | 0.963 |
| Molprobity score | 1.84 | 1.86 |
| Molprobity clashscore, all atoms | 5.10 | 6.90 |
| Ramachandran outliers (%) | 0 | 0 |
| Ramachandran allowed (%) | 10.73 | 7.85 |
| Ramachandran favored (%) | 89.27 | 92.15 |
| Rotamer outliers (%) | 0.77 | 0.77 |
| Cβ outliers (%) | 0 | 0 |
| Model versus map | RecA–ssDNA complex | RecA–dsDNA complex |
| Correlation coefficient (mask) | 0.80 | 0.84 |
| Correlation coefficient (box) | 0.51 | 0.55 |
| Correlation coefficient (peaks) | 0.25 | 0.25 |
| Correlation coefficient (volume) | 0.80 | 0.84 |
| Correlation coefficient CC for ligands | 0.80 | 0.87 |