| 4QK8: reference: Structural insights into recognition of c-di-AMP by the ydaO riboswitch., Gao A, Serganov A, Nat Chem Biol. 2014 Sep;10(9):787-92. doi: 10.1038/nchembio.1607. Epub 2014 Aug, 3. PMID: 25086507 |
This OCA 
Structure page
uses Jmol,
developed by the Jmol Development Team
(documentation).