Hypoxia-inducible factor prolyl hydroxylase 2 has a high affinity for ferrous iron and 2-oxoglutarate

Regulation of the hypoxic response in humans is regulated by the post-translational hydroxylation of hypoxia inducible transcription factor; a recombinant form of a human prolyl-4-hydroxylase (PHD2) was characterised and shown to have an unexpectedly high affinity for, and to copurify with endogenous levels of, its Fe(II) cofactor and 2-oxoglutarate cosubstrate.