3I2Q:
reference: Single-atom imino substitutions at A9 and A10 reveal distinct effects on the fold and function of the hairpin ribozyme catalytic core., Spitale RC, Volpini R, Mungillo MV, Krucinska J, Cristalli G, Wedekind JE, Biochemistry. 2009 Aug 25;48(33):7777-9. PMID: 19634899

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