3SD3:
reference: The Structure of a Tetrahydrofolate-Sensing Riboswitch Reveals Two Ligand Binding Sites in a Single Aptamer., Trausch JJ, Ceres P, Reyes FE, Batey RT, Structure. 2011 Sep 7. PMID: 21906956

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