COX 2, His-Tag (CPOX) Active Protein

The protein encoded by this gene is the sixth enzyme of the heme biosynthetic pathway. The encoded enzyme is soluble and found in the intermembrane space of mitochondria. This enzyme catalyzes the stepwise oxidative decarboxylation of coproporphyrinogen III to protoporphyrinogen IX, a precursor of heme. Defects in this gene are a cause of hereditary coproporphyria (HCP).[provided by RefSeq, Oct 2009]

CPOX: Key enzyme in heme biosynthesis. Catalyzes the oxidative decarboxylation of propionic acid side chains of rings A and B of coproporphyrinogen III. Defects in CPOX are the cause of hereditary coproporphyria (HCP). HCP is an acute hepatic porphyria and an autosomal dominant disease characterized by neuropsychiatric disturbances and skin photosensitivity. Biochemically, there is an overexcretion of coproporphyrin III in the urine and in the feces. HCP is clinically characterized by attacks of abdominal pain, neurological disturbances, and psychiatric symptoms. The symptoms are generally manifested with rapid onset, and can be precipitated by drugs, alcohol, caloric deprivation, infection, endocrine factors or stress. A severe variant form is harderoporphyria, which is characterized by earlier onset attacks, massive excretion of harderoporphyrin in the feces, and a marked decrease of coproporphyrinogen IX oxidase activity. Belongs to the aerobic coproporphyrinogen-III oxidase family.

Protein type: Mitochondrial; EC 1.3.3.3; Cofactor and Vitamin Metabolism - porphyrin and chlorophyll; Oxidoreductase

Chromosomal Location of Human Ortholog: 3q12

Cellular Component: mitochondrion; mitochondrial inner membrane; cytoplasm; mitochondrial intermembrane space

Molecular Function: coproporphyrinogen oxidase activity; protein homodimerization activity; structural constituent of eye lens

Biological Process: response to arsenic; response to methylmercury; response to lead ion; porphyrin metabolic process; response to insecticide; protoporphyrinogen IX biosynthetic process; response to iron ion; heme biosynthetic process

Disease: Coproporphyria, Hereditary