3OKG:
reference: Structure of HsdS subunit from Thermoanaerobacter tengcongensis sheds lights on mechanism of dynamic opening and closing of type I methyltransferase., Gao P, Tang Q, An X, Yan X, Liang D, PLoS One. 2011 Mar 2;6(3):e17346. PMID: 21399684

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