CATH Classification
Level | CATH Code | Description |
---|---|---|
3 | Alpha Beta | |
3.30 | 2-Layer Sandwich | |
3.30.160 | Double Stranded RNA Binding Domain | |
3.30.160.40 | Porphobilinogen deaminase, C-terminal domain |
Domain Context
CATH Clusters
Superfamily | Porphobilinogen deaminase, C-terminal domain |
Functional Family | Porphobilinogen deaminase |
Enzyme Information
2.5.1.61 |
Hydroxymethylbilane synthase.
based on mapping to UniProt Q43316
4 porphobilinogen + H(2)O = hydroxymethylbilane + 4 NH(3).
-!- The enzyme works by stepwise addition of pyrrolylmethyl groups until a hexapyrrole is present at the active center. -!- The terminal tetrapyrrole is then hydrolyzed to yield the product, leaving a cysteine-bound dipyrrole on which assembly continues. -!- In the presence of a second enzyme, EC 4.2.1.75, which is often called cosynthase, the product is cyclized to form uroporphyrinogen III. -!- If EC 4.2.1.75 is absent, the hydroxymethylbilane cyclizes spontaneously to form uroporphyrinogen I. -!- Formerly EC 4.3.1.8.
|
UniProtKB Entries (1)
Q43316 |
HEM3_ARATH
Arabidopsis thaliana
Porphobilinogen deaminase, chloroplastic
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PDB Structure
PDB | 4HTG |
External Links | |
Method | X-RAY DIFFRACTION |
Organism | |
Primary Citation |
Insights into the mechanism of pyrrole polymerization catalysed by porphobilinogen deaminase: high-resolution X-ray studies of the Arabidopsis thaliana enzyme.
Acta Crystallogr.,Sect.D
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