2LSN:
reference: The solution structure of the prototype foamy virus RNase H domain indicates an important role of the basic loop in substrate binding., Leo B, Schweimer K, Rosch P, Hartl MJ, Wohrl BM, Retrovirology. 2012 Sep 10;9:73. PMID: 22962864

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