Table 1.
Data Collection and Refinement Statistics for Vβ Variants
| S54N | A52V/S54N/K66E | V52A-r | E66K-r | H72Q-r | L2CM | |
|---|---|---|---|---|---|---|
| Data Collection | ||||||
| Space group | I212121 | I212121 | C2 | I212121 | I212121 | I212121 |
| Unit cell dimensions | ||||||
| a (Å), b (Å), c (Å) | 32.502, 74.834, 113.530 | 31.608, 74.708, 113.819 | 79.423, 116.295, 34.769; γ (°) = 110.17 | 32.502, 74.696, 113.591 | 32.521, 74.552, 113.045 | 32.528, 74.575, 113.083 |
| Molecules per asymmetric unit | 1 | 1 | 2 | 1 | 1 | 1 |
| Resolution (Å) | 30.00–1.80 | 30.00–1.80 | 40.00–2.00 | 30.00–1.90 | 30.00–2.00 | 30.00–1.80 |
| Observations | 67,564 | 54,289 | 85,921 | 63,425 | 49,693 | 76,325 |
| Unique reflections | 10,932 (651) | 11,549 (660) | 17,516 (922) | 10,640 (771) | 9,148 (648) | 12,398 (881) |
| Completeness (%) | 86.6 (73.2)a | 94.1 (73.8) | 92.36 (65.37) | 99.1 (99.6) | 99.1 (97.5) | 99.03 (97.9) |
| Rmerge (%)b | 6.8 (29.7) | 8.9 (35.4) | 5.3 (24.6) | 7.8 (30.3) | 4.8 (27.1) | 6.6 (23.6) |
| Refinement | ||||||
| Rcryst (%)c | 19.1 (35.5) | 19.7 (25.0) | 17.6 (28.3) | 18.9 (32.5) | 19.9 (21.2) | 19.0 (32.6) |
| Rfree (%)d | 25.8 (45.7) | 26.3 (28.1) | 21.3 (30.9) | 23.0 (35.7) | 23.9 (30.5) | 23.1 (27.1) |
| Protein residues | 110 | 112 | 218 | 109 | 109 | 109 |
| Water molecules | 144 | 151 | 102 | 162 | 110 | 190 |
| Average B factors (Å2) | ||||||
| Vβ | 17.2 | 26.0 | 38.8 | 17.9 | 15.1 | 16.3 |
| Water | 30.8 | 40.4 | 55.3 | 32.3 | 26.8 | 34.6 |
| Rms deviations | ||||||
| Bonds (Å) | 0.015 | 0.015 | 0.018 | 0.018 | 0.017 | 0.015 |
| Angles (°) | 1.341 | 1.526 | 1.878 | 1.507 | 1.639 | 1.353 |
| Ramachandran plot statistics | ||||||
| Core (%) | 91.2 | 90.3 | 91.8 | 91.2 | 91.2 | 90.1 |
| Allowed (%) | 8.8 | 9.7 | 8.2 | 8.8 | 8.8 | 9.9 |
| Generous (%) | 0 | 0 | 0 | 0 | 0 | 0 |
| Disallowed (%) | 0 | 0 | 0 | 0 | 0 | 0 |
Values in parentheses correspond to the highest-resolution shell: S54N (1.85–1.80 Å); A52V/S54N/K66E (1.85–1.80 Å); V52A-r (2.05–2.00 Å); E66K-r (1.95–1.90 Å); H72Q-r (2.05–2.00 Å); L2CM (1.85–1.80 Å).
Rmerge (I) = (Σ|I[i] − <I[h]>|/ΣI[i]), where I[i] is the ith observation of the intensity of the hkl reflection and <I> is the mean intensity from multiple measurements of the hkl reflection.
Rcryst (F) = Σh||Fobs(h)| − |Fcalc(h)||/Σh. |Fobs(h)| and |Fcalc(h)| are the observed and calculated, respectively, structure factor amplitudes for the hkl reflection.
Rfree is calculated over reflections in a test set not included in atomic refinement: S54N, 561 reflections, 4.9%; A52V/S54N/K66E, 630 reflections, 5.2%; V52A-r, 960 reflections, 5.2%; E66K-r, 574 reflections, 5.1%; H72Q-r, 465 reflections, 4.8%; L2CM, 682 reflections, 5.2%.