Cysteine dioxygenase

Cysteine dioxygenase (CDO,CAS number: 37256-59-0)) is a mammalian non-heme iron enzyme that catalyzes the conversion of L-cysteine to cysteine sulfinic acid (cysteine sulfinate) by incorporation of dioxygen.



Cysteine sulfinic acid lies at a branch-point in cysteine catabolism, where it can follow two pathways resulting in the formation of taurine or sulfate. The cysteine sulfinic acid dependent pathway of taurine metabolism follows the synthesis of hypotaurine (2-aminoethane sulfinate), which is subsequently oxidized to taurine. Alternatively, cysteine sulfinate can undergo transamination to form β-sulfinylpyruvate, decomposing to form pyruvate and sulfite.