Figure 3.

CDO1 catalyzes the metabolic pathway of cysteine. CDO1 can transfer two oxygen atoms of oxygen to the sulfur of cysteine, forming CSA. CSA is converted to hypotaurine by CSAD; hypotaurine is eventually oxidated to taurine by HDH. In addition, CSA is transaminated by GOT1 to produce β-sulfinylpyruvate, which spontaneously dissociates to give rise to pyruvate and sulfite. Sulfite is further oxidized to ${\text{SO}}_4^{2-}$by SUOX. On the other hand, CDO1 reduces the synthesis of GSH and H₂S by promoting cysteine metabolism. CSA, cysteine sulfinic acid CSAD, cysteine sulfinate decarboxylase; HDH, hypotaurine dehydrogenase; GOT1, cytosolic aspartate aminotransferase; ${\text{SO}}_4^{2-}$, sulfate; SUOX, sulfite oxidase.