| 4G6R: reference: A Transition-State Interaction Shifts Nucleobase Ionization toward Neutrality To Facilitate Small Ribozyme Catalysis., Liberman JA, Guo M, Jenkins JL, Krucinska J, Chen Y, Carey PR, Wedekind JE, J Am Chem Soc. 2012 Oct 17;134(41):16933-6. doi: 10.1021/ja3070528. Epub 2012 Oct, 3. PMID: 22989273 |
This OCA 
Structure page
uses Jmol,
developed by the Jmol Development Team
(documentation).