This family contains members of the 2-oxoglutarate (2OG) and Fe(II)-dependent oxygenase superfamily [1]. This family includes the C-terminal of prolyl 4-hydroxylase alpha subunit. The holoenzyme has the activity EC:1.14.11.2 catalysing the reaction: Procollagen L-proline + 2-oxoglutarate + O2 <=> procollagen trans- 4-hydroxy-L-proline + succinate + CO2. The full enzyme consists of a alpha2 beta2 complex with the alpha subunit contributing most of the parts of the active site [3]. The family also includes lysyl hydrolases, isopenicillin synthases and AlkB.

1: The DNA-repair protein AlkB, EGL-9, and leprecan define new families of 2-oxoglutarate- and iron-dependent dioxygenases. Aravind L, Koonin EV; Genome Biol 2001;2:RESEARCH0007. PMID:11276424

2: Cloning of the human prolyl 4-hydroxylase alpha subunit isoform alpha(II) and characterization of the type II enzyme tetramer. The alpha(I) and alpha(II) subunits do not form a mixed alpha(I)alpha(II)beta2 tetramer. Annunen P, Helaakoski T, Myllyharju J, Veijola J, Pihlajaniemi T, Kivirikko KI; J Biol Chem 1997;272:17342-17348. PMID:9211872

3: Cloning, baculovirus expression, and characterization of a second mouse prolyl 4-hydroxylase alpha-subunit isoform: formation of an alpha 2 beta 2 tetramer with the protein disulfide-isomerase/beta subunit. Helaakoski T, Annunen P, Vuori K, MacNeil IA, Pihlajaniemi T, Kivirikko KI; Proc Natl Acad Sci U S A 1995;92:4427-4431. PMID:7753822

4: Crystal structure of isopenicillin N synthase is the first from a new structural family of enzymes. Roach PL, Clifton IJ, Fulop V, Harlos K, Barton GJ, Hajdu J, Andersson I, Schofield CJ, Baldwin JE; Nature 1995;375:700-704. PMID:7791906