Table 1. Crystal Data, Data Collection, and Refinement Statistics.

space group	orthorhombic P212121
cell parameters (Å)	a = 25.64, b = 40.31, c = 65.93
temperature of data collection (° C)	–170
wavelength (Å)	0.9785
max resolution (Å)	1.1
unique reflections	27920
completeness all/1.14–1.10 Å (%)	97.8/95.8
redundancy all/1.14–1.1 Å	10.6/6.9
I/σ (I) all/1.14–1.1 Å	61.26/4.8
Rmerge all/1.14–1.10 Å	0.048/0.394
Rwork	0.161
Rfree	0.195
number of DNA atoms	486
number of water molecules	133
number of ions	1 Mg2+
	4 Na+
rms distances (Å)	0.024
rms angles (°)	1.95