Recombinant Human UROS protein

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

Uroporphyrinogen III synthase commonly known as UROS is an enzyme involved in heme biosynthesis. It catalyzes the conversion of hydroxymethylbilane to uroporphyrinogen III facilitating a ring closure and isomerization. UROS has a molecular mass of approximately 29 kDa. It is predominantly expressed in the liver bone marrow and erythroid tissues where heme production is essential. The enzyme is vital for maintaining proper levels of porphyrins in cells and ensuring the biosynthesis of heme an important component of hemoglobin.

Biological function summary

Uroporphyrinogen III synthase plays a role in heme production converting linear tetrapyrroles into the cyclic form needed for biosynthesis. This enzyme does not function as part of a larger complex but rather works independently to catalyze its specific reaction in porphyrin metabolism. Proper function of UROS is necessary to sustain the production of heme which is critical not only for oxygen transport in the blood but also for other heme-dependent processes in various tissues.

Pathways

UROS is an essential component of the heme biosynthesis pathway. In this pathway it acts between the steps that involve hydroxymethylbilane synthase (HMBS) and uroporphyrinogen III decarboxylase (UROD). This metabolic pathway is important for the production of heme which is a core component of hemoglobin. HMBS synthesizes the precursor transformed by UROS while UROD further modifies the product of UROS to continue the biosynthesis process emphasizing the enzyme's importance in maintaining the heme biosynthesis pathway's integrity.

Mutations or deficiencies in UROS are linked to a rare inherited condition called congenital erythropoietic porphyria (CEP) also known as Günther's disease. This disorder results from the accumulation of porphyrins owing to impaired heme biosynthesis. Abnormal function in UROS leads to a buildup of its substrates causing severe skin photosensitivity and hemolytic anemia among other symptoms. The functional relationship between UROS and HMBS or UROD in the heme biosynthesis pathway illustrates the enzyme's significant role in preventing the development of such heme-related disorders.