Catalyzes the oxidation of sulfhydryl groups in peptide and protein thiols to disulfides with the reduction of oxygen to hydrogen peroxide. May contribute to disulfide bond formation in a variety of secreted proteins. In fibroblasts, it may have tumor-suppressing capabilities being involved in growth regulation.
Expressed in heart, placenta, lung, liver, skeletal muscle, pancreas and very weakly in brain and kidney.
Belongs to the quiescin-sulfhydryl oxidase (QSOX) family. Contains 1 ERV/ALR sulfhydryl oxidase domain. Contains 1 thioredoxin domain.
Golgi apparatus membrane and Secreted > extracellular space. Found in the extracellular medium of quiescent cells but is not found in proliferating cells.