CATH Classification
| Level | CATH Code | Description |
|---|---|---|
|
3 | Alpha Beta |
|
3.40 | 3-Layer(aba) Sandwich |
|
3.40.190 | D-Maltodextrin-Binding Protein; domain 2 |
|
3.40.190.10 | Periplasmic binding protein-like II |
Domain Context
CATH Clusters
| Superfamily | Periplasmic binding protein-like II |
| 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
|
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
|
