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Uroporphyrinogen III Synthetase MeSH Descriptor Data 2025


MeSH Heading
Uroporphyrinogen III Synthetase
Tree Number(s)
D08.811.520.241.300.950
Unique ID
D014576
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D014576
Scope Note
An enzyme that catalyzes the cyclization of hydroxymethylbilane to yield UROPORPHYRINOGEN III and water. It is the fourth enzyme in the 8-enzyme biosynthetic pathway of HEME, and is encoded by UROS gene. Mutations of UROS gene result in CONGENITAL ERYTHROPOIETIC PORPHYRIA.
Entry Term(s)
Cosynthase
Uroporphyrinogen III Cosynthetase
Uroporphyrinogen Isomerase
Uroporphyrinogen-III Synthase
Registry Numbers
EC 4.2.1.75
Related Numbers
37340-55-9
CAS Type 1 Name
Hydroxymethylbilane hydro-lyase (cyclizing)
Previous Indexing
Isomerases (1971-1974)
Porphobilinogen (1973-1974)
See Also
Porphyria, Erythropoietic
Public MeSH Note
2005; see UROPORPHYRINOGEN-III SYNTHASE 1998-2004, see UROPORPHYRINOGEN III SYNTHASE 1991-1997, see HYDRO-LYASES 1985-1990, see ISOMERASES 1975-1984
History Note
2005 (1975)
Entry Combination
deficiency:Porphyria, Erythropoietic
Date Established
1991/01/01
Date of Entry
1974/11/19
Revision Date
2009/07/06
Uroporphyrinogen III Synthetase Preferred
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