Fig 2.

Analysis of interacting molecules in the two different crystalline lattices. (A) Possible pairs of interacting molecules are shown for the form I lattice, one in a head-to-tail arrangement shown as backbone traces in green and cyan and the other in a head-to-head arrangement in blue and cyan. (B) The two molecules in the asymmetric unit of the form II lattice are packed in a head-to-tail arrangement shown in cyan and green. The cyan molecule is shown in a similar orientation to that of the cyan molecule in A. Although there are head-to-tail arrangements in both the form I and II lattices, the details of the interactions between the two molecules differ significantly as seen readily by comparing the relative positions of the green molecules in the two lattices. The residues involved in DNA binding are highlighted in red for the trace renderings of each molecule in both A and B.