Table I.
Summary of Crystal Parameters, Data Collection, and Refinement Statistics for YtaA (PDB ID: 2Q83)
| Space group | P6422 | ||
| Unit cell parameters | a = b = 173.00, c = 192.57 Å | ||
| Data collection | λ1 MAD-Se | λ2 MAD-Se | λ3 MAD-Se |
| Wavelength (Å) | 0.9116 | 0.9792 | 0.9791 |
| Resolution range (Å) | 29.96–2.50 | 29.96–2.50 | 29.99–2.71 |
| Number of observations | 639,503 | 631,260 | 511,467 |
| Number of unique reflections | 59,155 | 59,113 | 46,847 |
| Completeness (%) | 99.9 (100.0)a | 99.9 (100.0) | 99.9 (100.0) |
| Mean I/σ(I) | 17.0 (3.0)a | 17.2 (2.5) | 14.2 (1.9) |
| Rsym on I (%) | 12.6 (86.4)a | 12.5 (86.9) | 16.9 (1.398) |
| Highest resolution shell (Å) | 2.56–2.50 | 2.56–2.50 | 2.78–2.71 |
| Model and refinement statistics | |||
| Resolution range (Å) | 29.96–2.50 | Dataset used in refinement | λ1 MADSe |
| Number of reflections (total) | 59,108b | Cutoff criteria | |F| > 0 |
| Number of reflections (test) | 2988 | Rcryst | 0.198 |
| Completeness (% total) | 100.0 | Rfree | 0.210 |
| Stereochemical parameters | |||
| Restraints (RMS observed) | |||
| Bond length (Å) | 0.012 | ||
| Bond angle (°) | 1.66 | ||
| Average isotropic B-value (Å2) | 40.7 | ||
| ESU based on Rfree value (Å) | 0.169 | ||
| Protein residues/atoms | 332/5615 | ||
| Water molecules | 185 | ||
Highest resolution shell.
Typically, the number of unique reflections used in refinement is slightly less than the total number that were integrated and scaled. Reflections are excluded due to systematic absences, negative intensities, and rounding errors in the resolution limits and cell parameters.
ESU, estimated overall coordinate error18,19; Rsym, Σ|Ii – <Ii>|/Σ|Ii|, where Ii is the scaled intensity of the ith measurement and <Ii> is the mean intensity for that reflection; Rcryst, Σ| |Fobs| – |Fcalc| |/Σ|Fobs|, where Fcalc and Fobs are the calculated and observed structure factor amplitudes, respectively; Rfree, as for Rcryst, but for 4.9% of the total reflections chosen at random and omitted from refinement.