3KIH:
reference: Metamorphic proteins mediate evolutionary transitions of structure., Yadid I, Kirshenbaum N, Sharon M, Dym O, Tawfik DS, Proc Natl Acad Sci U S A. 2010 Apr 20;107(16):7287-92. Epub 2010 Apr 5. PMID: 20368465

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