2RNT:
reference: Three-dimensional structure of ribonuclease T1 complexed with guanylyl-2',5'-guanosine at 1.8 A resolution., Koepke J, Maslowska M, Heinemann U, Saenger W, J Mol Biol 1989 Apr 5;206(3):475-88. PMID: 2541256

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