Cannabidiolic acid synthase
From Wikipedia, the free encyclopedia
Cannabidiolic acid synthase (EC 1.21.3.8, CBDA synthase) is an enzyme with systematic name cannabigerolate:oxygen oxidoreductase (cyclizing, cannabidiolate-forming).[1][2] It is an oxidoreductase found in Cannabis sativa that catalyses the formation of cannabidiolate, a carboxylated precursor of cannabidiol.[2]
| Cannabidiolic acid synthase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC no. | 1.21.3.8 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| |||||||||
Enzyme structure
Cannabidiolic acid synthase consists of a single protein with a molecular mass of 74 kDa.[1] Its amino acid sequence is partly (40-50%) homologous to several other oxidoreductases,[2] such as berberine bridge enzyme in Eschscholzia californica[3] and Nectarin V in Nicotiana langsdorffii X N. sanderae.[4]
CBDA synthase has four binding sites; two for FAD and two for the substrate.[5]
Enzyme function
Cannabidiolic acid synthase catalyses the production of cannabidiolate predominantly from cannabigerolate by stereospecific oxidative cyclization of the geranyl group of cannabigerolic acid[2] according to the following chemical reaction:
- cannabigerolate + O2 → cannabidiolate + H2O2
Cannabinerolate can also be used as a substrate, but with lower efficiency (KM=0.137 mM) than cannabigerolate (KM=0.206 mM). It covalently binds FAD, and does require coenzymes & molecular oxygen for the oxidocyclization reaction.[1]
The optimum pH for CBDA synthase is 5.0.[2]
