1KHV:
reference: Crystal structures of active and inactive conformations of a caliciviral RNA-dependent RNA polymerase., Ng KK, Cherney MM, Vazquez AL, Machin A, Alonso JM, Parra F, James MN, J Biol Chem 2002 Jan 11;277(2):1381-7. PMID: 11677245

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