4KFS:
reference: The structure of the NTPase that powers DNA packaging into Sulfolobus turreted icosahedral virus 2., Happonen LJ, Oksanen E, Liljeroos L, Goldman A, Kajander T, Butcher SJ, J Virol. 2013 May 22. PMID: 23698307

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