Crystal structure of PHYHD1A, a 2OG oxygenase related to phytanoyl-CoA hydroxylase

► Human PHYHD1A has the double-stranded β-helix fold and Fe(II) and cosubstrate binding residues characteristic of the 2-oxoglutarate dependent oxygenases. ► Human PHYHD1A catalyzes the conversion of 2-oxoglutarate to succinate and CO2 in an iron-dependent manner. ► The PHYHD1 B and C isoforms are likely not active as 2OG oxygenases. ► PHYHD1 does not catalyze the hydroxylation of phytanoyl-CoA unlike its closest homologue PAHX.