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uroporphyrinogen-III synthase; UROIIIS; UROS; hydroxymethylbilane hydrolyase [cyclizing]; uroporphyrinogen-III cosynthase (UROS)

Function: - catalyzes cyclization of the linear tetrapyrrole, hydroxymethylbilane, to the macrocyclic uroporphyrinogen III, the branch point for various sub-pathways leading to a diversity of porphyrins - porphyrins act as cofactors for many enzymes including methionine synthesis (vitamin B12) or oxygen transport (heme) - porphyrin metabolism; protoporphyrin-IX biosynthesis - coproporphyrinogen-III from 5-aminolevulinate: step 3/4 hydroxymethylbilane = uroporphyrinogen III + H2O Structure: - monomer - belongs to the uroporphyrinogen-III synthase family Expression: ubiquitous Pathology: - defects in UROS are the cause of congenital erythropoietic porphyria

Interactions

molecular events

General

hydro-lyase, hydratase or dehydratase

Properties

SIZE: entity length = 265 aa MW = 29 kD MOTIF: active site

Database Correlations

OMIM correlations MORBIDMAP 606938 UniProt P10746 Pfam PF02602 Entrez Gene 7390 Kegg hsa:7390 ENZYME 4.2.1.75

References

  1. UniProt :accession P10746
  2. GeneReviews http://www.ncbi.nlm.nih.gov/sites/genetests/lab/gene/UROS
  3. Textbook of Biochemistry with Clinical Correlations, 3rd ed., TM Devlin (ed), Wiley-Liss, NY 1992 pg 1013