In enzymology, a 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase (HMB-PP synthase, IspG, EC 1.17.7.1) is an enzyme that catalyzes the chemical reaction
| 4-hydroxy-3-methylbut-2-en-1-yl diphosphate synthase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 1.17.7.1 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
- 2-C-methyl-D-erythritol 2,4-cyclodiphosphate + protein-dithiol (E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate + H2O + protein-disulfide
The substrate of this enzyme is 2-C-methyl-D-erythritol 2,4-cyclodiphosphate (MEcPP) and the product is (E)-4-hydroxy-3-methylbut-2-en-1-yl diphosphate (HMB-PP). Electrons are donated by two reduced ferredoxin proteins per reaction.
This enzyme participates in the MEP pathway (non-mevalonate pathway) of Isoprenoid precursor biosynthesis.
Nomenclature
editThis enzyme belongs to the family of oxidoreductases, specifically those acting on CH or CH2 groups with a disulfide as acceptor. The systematic name of this enzyme class is (E)-4-hydroxy-3-methylbut-2-en-1-yl-diphosphate:protein-disulfide oxidoreductase (hydrating).
References
editFurther reading
edit- Hecht S, Eisenreich W, Adam P, Amslinger S, Kis K, Bacher A, Arigoni D, Rohdich F (December 2001). "Studies on the nonmevalonate pathway to terpenes: the role of the GcpE (IspG) protein". Proceedings of the National Academy of Sciences of the United States of America. 98 (26): 14837–42. Bibcode:2001PNAS...9814837H. doi:10.1073/pnas.201399298. PMC 64945. PMID 11752431.
