1I9H:
reference: Chicken avidin exhibits pseudo-catalytic properties. Biochemical, structural, and electrostatic consequences., Huberman T, Eisenberg-Domovich Y, Gitlin G, Kulik T, Bayer EA, Wilchek M, Livnah O, J Biol Chem 2001 Aug 24;276(34):32031-9. PMID: 11395489

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