Table 1. Data collection and refinement statistics.
| pH 6.0 | pH 7.6 | pH 8.0 | CMK complex | |
|---|---|---|---|---|
| Data collection statistics | ||||
| Wavelength, Å | 0.9801 | 0.9801 | 0.9801 | 0.9801 |
| Resolution limit, Å | 50.0—1.9 (1.97—1.90) | 50.0—2.4 (2.49—2.40) | 50.0—2.2 (2.28—2.20) | 50.0—2.5 (2.54—2.50) |
| Cell parameters | ||||
| a, Å | 52.8 | 49.3 | 49.5 | 52.6 |
| b, Å | 97.2 | 97.0 | 97.4 | 97.7 |
| c, Å | 67.7 | 67.8 | 67.5 | 67.9 |
| β, ° | 103.1 | 101.9 | 101.7 | 102.8 |
| Total reflections | 190,084 | 83,091 | 119,770 | 78,378 |
| Unique reflections | 51,775 | 24,261 | 31,275 | 22,614 |
| Completeness | 99.9 (99.5) | 99.3 (94.7) | 100.0 (100.0) | 98.4 (96.3) |
| Redundancy | 3.7 (3.6) | 3.7 (3.7) | 4.4 (4.4) | 4.2 (4.1) |
| Rmerge* | 0.107 (0.570) | 0.132 (0.652) | 0.108 (0.484) | 0.104 (0.444) |
| I/σ(I) | 10.4 (3.7) | 9.8 (3.3) | 10.5 (3.3) | 7.3 (3.1) |
| Refinement statistics | ||||
| Resolution range | 30.0-1.9 | 50.0-2.4 | 50.0-2.2 | 50.0-2.5 |
| Rwork† % | 21.1 | 22.9 | 22.6 | 21.6 |
| Rfree, % | 25.9 | 24.8 | 25.3 | 26.4 |
| rms deviation from ideal geometry | ||||
| Bonds, Å | 0.013 | 0.012 | 0.020 | 0.008 |
| Angles, ° | 1.75 | 1.57 | 2.31 | 1.40 |
| Average B factor, Å2 | ||||
| Chain A | 28.4 | 30.5 | 32.6 | 38.5 |
| Chain B | 28.1 | 36.0 | 36.3 | 37.8 |
| Solvent | 38.2 | 34.3 | 34.6 | 36.8 |
| Ramachandran plot‡ | ||||
| Favored, % | 89.3 | 81.5 | 84.4 | 82.4 |
| Allowed, % | 8.8 | 15.7 | 13.0 | 15.5 |
| Generously allowed, % | 1.0 | 1.7 | 1.5 | 1.0 |
| Disallowed, % | 1.0 | 1.1 | 1.1 | 1.1 |
*
Rmerge = Σh Σl|Iih — 
, where 
is the mean of the observations, Iih, of reflection h
†
Rwork = Σ (∥Fobs| — Fcalc∥)/Σ|Fobs|; Rfree is the R factor for a subset (10%) of reflections that was selected prior to refinement calculations and was not included in the refinement
‡
Ramachandran plots were generated by using the program PROCHECK (14)