2V9P:
reference: Papillomavirus E1 helicase assembly maintains an asymmetric state in the absence of DNA and nucleotide cofactors., Sanders CM, Kovalevskiy OV, Sizov D, Lebedev AA, Isupov MN, Antson AA, Nucleic Acids Res. 2007 Sep 19;. PMID: 17881379

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