Ferroxidase

Ferroxidase also known as Fe(II):oxygen oxidoreductase is an enzyme that catalyzes the oxidization of iron II to iron III:
 * 4 Fe2+ + 4 H+ + O2 ⇔ 4 Fe3+ + 2H2O

Examples
Human genes encoding proteins with ferroxidase activity include:
 * CP – Ceruloplasmin
 * FTH1 – Ferritin heavy chain
 * FTMT – Ferritin, mitochondrial
 * HEPH - Hephaestin