Evidence that two enzyme-derived histidine ligands are sufficient for iron binding and catalysis by factor inhibiting HIF (FIH).Hewitson, K.S., Holmes, S.L., Ehrismann, D., Hardy, A.P., Chowdhury, R., Schofield, C.J., McDonough, M.A.
(2008) J.Biol.Chem. 283: 25971-25978
- PubMed: 18611856
- DOI: 10.1074/jbc.M804999200
- Primary Citation of Related Structures:
- PubMed Abstract:
- Structure of Factor-Inhibiting Hypoxia-Inducible Factor (Hif) Reveals Mechanism of Oxidative Modification of Hif-1 Alpha
Elkins, J.M.,Hewitson, K.S.,Mcneill, L.A.,Seibel, J.F.,Schlemminger, I.,Pugh, C.W.,Ratcliffe, P.J.,Schofield, C.J.
(2003) J.Biol.Chem. 278: 1802
- Selective Inhibition of Factor Inhibiting Hypoxia Inducible Factor
Mcdonough, M.A.,Mcneill, L.A.,Tilliet, M.,Papamicael, C.A.,Chen, Q.Y.,Banerji, B.,Hewitson, K.S.,Schofield, C.J.
(2005) J.Am.Chem.Soc. 127: 7680
A 2-His-1-carboxylate triad of iron binding residues is present in many non-heme iron oxygenases including the Fe(II) and 2-oxoglutarate (2OG)-dependent dioxygenases. Three variants (D201A, D201E, and D201G) of the iron binding Asp-201 residue of an ...
A 2-His-1-carboxylate triad of iron binding residues is present in many non-heme iron oxygenases including the Fe(II) and 2-oxoglutarate (2OG)-dependent dioxygenases. Three variants (D201A, D201E, and D201G) of the iron binding Asp-201 residue of an asparaginyl hydroxylase, factor inhibiting HIF (FIH), were made and analyzed. FIH-D201A and FIH-D201E did not catalyze asparaginyl hydroxylation, but in the presence of a reducing agent, they displayed enhanced 2OG turnover when compared with wild-type FIH. Turnover of 2OG by FIH-D201A was significantly stimulated by the addition of HIF-1alpha(786-826) peptide. Like FIH-D201A and D201E, the D201G variant enhanced 2OG turnover but rather unexpectedly catalyzed asparaginyl hydroxylation. Crystal structures of the FIH-D201A and D201G variants in complex with Fe(II)/Zn(II), 2OG, and HIF-1alpha(786-826/788-806) implied that only two FIH-based residues (His-199 and His-279) are required for metal binding. The results indicate that variation of 2OG-dependent dioxygenase iron-ligating residues as a means of functional assignment should be treated with caution. The results are of mechanistic interest in the light of recent biochemical and structural analyses of non-heme iron and 2OG-dependent halogenases that are similar to the FIH-D201A/G variants in that they use only two His-residues to ligate iron.
Chemistry Research Laboratory, The Department of Chemistry, University of Oxford, Mansfield Road, Oxford OX1 3TA, United Kingdom.