2NPY:
reference: A posteriori design of crystal contacts to improve the X-ray diffraction properties of a small RNA enzyme., MacElrevey C, Spitale RC, Krucinska J, Wedekind JE, Acta Crystallogr D Biol Crystallogr. 2007 Jul;63(Pt 7):812-25. Epub 2007, Jun 15. PMID: 17582172

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