2DE8:
reference: Tris(hydroxymethyl)aminomethane induces conformational change and crystal-packing contraction of porcine pancreatic elastase., Kinoshita T, Yamaguchi A, Tada T, Acta Crystallograph Sect F Struct Biol Cryst Commun. 2006 Jul 1;62(Pt, 7):623-6. Epub 2006 Jun 26. PMID: 16820677

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