Table 1.
Data collection, phasing, and refinement statistics
| Data collection and phasing | |||
| Data set | Native | Pb1 | D38C (KCl) |
| Space group | I222 | I222 | I222 |
| Unit cell parameters, Å | |||
| a | 61.8 | 61.8 | 60.5 |
| b | 110.2 | 110.9 | 109.3 |
| c | 152.3 | 151.7 | 151.9 |
| Temperature, K | 290 | 290 | 100 |
| Resolution, Å | 2.00 | 1.90 | 1.60 |
| Highest resolution shell, Å | 2.05–2.00 | 1.94–1.90 | 1.64–1.60 |
| Rmerge, %*† | 0.062 (0.309) | 0.079 (0.51) | 0.058 (0.592) |
| Completeness, %† | 92.0 (95.8) | 99.3 (99.9) | 99.1 (98.2) |
| No. unique reflections | 32,706 | 41,139 | 66,155 |
| I/σI† | 15.99 (3.05) | 17.06 (2.34) | 25.80 (2.70) |
| MFID, %‡ | 0.218 | ||
| Phasing power (acentric/ centric)§ | 1.56/1.23 | ||
| Rcullis, acentric/centric¶ | 0.75/0.66 | ||
| Number of sites | 1 | ||
| Refinement | |||
| No. of reflections used | 29,565 | 62,796 | |
| Rcryst, %/Rfree, % | 16.1/20.7 | 15.4/18.6 | |
| Ramachandran plot, % | 88.9/10.4/0.7 | 89.4/10.0/0.7 | |
| Rms deviation bond length, Å | 0.012 | 0.023 | |
| Rms deviation bond angle, ° | 1.58 | 1.55 | |
| Number in final model | |||
| Residues | 355 | 357 | |
| Protein atoms | 2749 | 2778 | |
| Catalytic Zn2+ | – | 1 | |
| Citrate ions | – | 1 | |
| NADP | 1 | 1 | |
| K+ | – | 5 | |
| Water molecules | 146 | 675 | |
| Mean B values, Å2 | |||
| Protein atoms | 34 | 25 | |
| Catalytic Zn2+ | – | 24 | |
| Citrate ion | – | 36 | |
| NADP | 32 | 24 | |
| K+ | – | 29 | |
| Waters | 44 | 41 |
*Rmerge = Σhkl|Ii − Im|/Σhkl1Im, where Im is the mean intensity of the reflection.
†Numbers in parentheses indicate values for the highest resolution shell.
‡Mean fractional isomorphous difference = Σ‖FPH| − |FP‖/Σ|FP|, where FPH and FP are the structure factor amplitudes for derivative and native crystals, respectively.
§Phasing power is defined as the rms value of heavy-atom structure factor amplitude divided by the rms value of lack-of-closure error.
¶Rcullis = 〈lack-of-closure〉/〈isomorphous difference〉.