Table 2.

X-ray data collection and refinement statistics

	CA XII	CA XII–acetazolamide complex
Total no. of reflections measured	402,312	636,087
No. of unique reflections	80,168	89,743
Resolution range, Å	30–1.55	50–1.50
Rsym* (last shell), %	4.6 (28.7)	5.3 (31.8)
Completeness (last shell), %	96.5 (79.3)	99.3 (95.4)
No. of reflections used for refinement	74,133	84,952
R factor†	0.194	0.190
Rfree‡	0.221	0.207
No. of nonhydrogen atoms§	4178	4169
No. of water molecules	537	504
rms deviations from ideality
Bond lengths, Å	0.005	0.005
Bond angles, °	1.3	1.4
Dihedral angles, °	24.6	24.4
Improper dihedral angles, °	0.76	0.75

^*R_sym = ∑ |I − 〈I〉|/∑ I, where I is the observed intensity and 〈I〉 is the average intensity over all observations of symmetry-related reflections. 

^† R factor = ∑ ∥F_obs| − |F_calc∥/∑ |F_obs|, where |F_obs| and |F_calc| are the observed and calculated structure factor amplitudes, respectively. 

^‡ R_free was calculated from a randomly chosen subset of 8% of the reflections excluded from refinement. 

^§For two molecules in the asymmetric unit.