439D:
reference: Structure of an RNA duplex with an unusual G.C pair in wobble-like conformation at 1.6 A resolution., Perbandt M, Vallazza M, Lippmann C, Betzel C, Erdmann VA, Acta Crystallogr D Biol Crystallogr 2001 Feb;57(Pt 2):219-24. PMID: 11173467

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