3T1H:
reference: Human tRNA(Lys3)(UUU) Is Pre-Structured by Natural Modifications for Cognate and Wobble Codon Binding through Keto-Enol Tautomerism., Vendeix FA, Murphy FV 4th, Cantara WA, Leszczynska G, Gustilo EM, Sproat B, Malkiewicz A, Agris PF, J Mol Biol. 2011 Dec 29. PMID: 22227389

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