Table 1. Crystal details, data collection and final refinement parameters.

Unit cell dimensions (Å)	a = b = 30.2, c = 39.3
Space group	P64
No. of observations	30 670
No. of unique reflections	1955
Resolution range (Å)	40–1.8
Rmerge (%)	9.4 (35.1)a
Completeness (%)	99.8 (100)a
I/σI	21.5 (5.0)a
No. of water molecules	17 full occupancy and three partial occupancy
R (%)	21.9
Rfree (%)	29.1
RMSD from ideal geometry of final model distances
Bonds (Å)	0.004 (0.03)b
Angles (Å)	0.012 (0.05)b
Planes (Å)	0.027 (0.10)b
Average B values (Å2)
Bases	25
Sugars	28
Phosphates	32
Intercalated ligand (100% occupancy)	29
Intercalated ligand side chain (66% occupancy)	49
End-stacked ligand (50% occupancy)	26
Water
Full occupancy	34
Partial occupancy	43

^aValues in parentheses are for the last shell, 1.86–1.80 Å.

^bTarget values are in parentheses.