3D8C:
reference: Evidence that two enzyme-derived histidine ligands are sufficient for iron binding and catalysis by factor inhibiting HIF (FIH)., Hewitson KS, Holmes SL, Ehrismann D, Hardy AP, Chowdhury R, Schofield CJ, McDonough MA, J Biol Chem. 2008 Sep 19;283(38):25971-8. Epub 2008 Jul 8. PMID: 18611856

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