2PUD:
reference: Crystal structure of LacI member, PurR, bound to DNA: minor groove binding by alpha helices., Schumacher MA, Choi KY, Zalkin H, Brennan RG, Science 1994 Nov 4;266(5186):763-70. PMID: 7973627

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).