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Hydroxymethylbilane Synthase MeSH Descriptor Data 2023


MeSH Heading
Hydroxymethylbilane Synthase
Tree Number(s)
D08.811.913.225.575
Unique ID
D011163
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D011163
Scope Note
An enzyme that catalyzes the tetrapolymerization of the monopyrrole PORPHOBILINOGEN into the hydroxymethylbilane preuroporphyrinogen (UROPORPHYRINOGENS) in several discrete steps. It is the third enzyme in the 8-enzyme biosynthetic pathway of HEME. In humans, deficiency in this enzyme encoded by HMBS (or PBGD) gene results in a form of neurological porphyria (PORPHYRIA, ACUTE INTERMITTENT). This enzyme was formerly listed as EC 4.3.1.8
Entry Term(s)
Hydroxymethylbilane Synthetase
Porphobilinogen Ammonia-Lyase
Porphobilinogen Deaminase
Pre-uroporphyrinogen Synthetase
Preuroporphyrinogen Synthetase
Uroporphyrinogen I Synthase
Registry Number
EC 2.5.1.61
Related Numbers
9036-47-9
CAS Type 1 Name
Porphobilinogen ammonia-lyase (polymerizing)
Previous Indexing
Ammonia-Lyases (1973-1974)
Porphobilinogen (1973-1974)
See Also
Porphyrias
Public MeSH Note
98; see PORPHOBILINOGEN DEAMINASE 1991-97, see AMMONIA-LYASES 1975-90
History Note
98(75)
Entry Combination
deficiency:Porphyria, Acute Intermittent
Date Established
1991/01/01
Date of Entry
1974/11/19
Revision Date
2009/07/06
Hydroxymethylbilane Synthase Preferred
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