2FHL:
reference: Factors dictating the pseudocatalytic efficiency of avidins., Prizant M, Eisenberg-Domovich Y, Hytonen VP, Kulomaa MS, Wilchek M, Bayer EA, Livnah O, J Mol Biol. 2006 May 5;358(3):754-63. Epub 2006 Mar 3. PMID: 16546211

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