These enzymes catalyze the incorporation of oxygen into organic substrates through a mechanism that requires alpha-Ketoglutaric acid, Fe2+, and ascorbate.

[1][2] This particular enzyme catalyzes the formation of (2S, 4R)-4-hydroxyproline, a compound that represents the most prevalent post-translational modification in the human proteome.

The second stage involves the abstraction of the pro-R hydrogen atom from C-4 of the proline substrate followed by radical combination, which yields hydroxyproline.

This succinate is hydrolyzed and replaced with another 2-oxoglutarate after each reaction, and it has been concluded that in the presence of 2-oxoglutarate, enzyme-bound Fe2+ is rapidly converted to Fe3+, leading to inactivation of the enzyme.

As prolyl hydroxylase requires ascorbate as a cofactor to function,[5] its absence compromises the enzyme’s activity.

Since stability of collagen is compromised in scurvy patients, symptoms include weakening of blood vessels causing purpura, petechiae, and gingival bleeding.