Table 2. Structure refinement and model composition.

	D4/A201–50-W43A	D4-R167A/A201–50	D4-P173G/A201–50
Resolution range (Å)	48.51–2.59	28.84–2.80	48.61–2.49
Completeness (%)	99.6	99.6	99.5
σ Cutoff	None	None	None
No. of reflections, working set	23039	18665	26112
No. of reflections, test set	1162	940	1306
Final R cryst	0.195	0.176	0.183
Final R free	0.250	0.233	0.238
No. of non-H atoms
Protein	4329	4323	4351
Ligand	30	30	33
Water	63	25	105
Total	4428	4378	4489
R.m.s. deviations
Bond lengths (Å)	0.015	0.015	0.017
Bond angles (°)	1.85	1.83	1.99
Average B factor (Å2)
Protein	64.9	54.9	58.3
Ramachandran plot (%)
Favoured regions	93	93	96
Additionally allowed regions	6	6	4
Outliers	1	1	0