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]
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 + H2 O2
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]
References
^ a b c Taura F, Morimoto S, Shoyama Y (July 1996). "Purification and characterization of cannabidiolic-acid synthase from Cannabis sativa L.. Biochemical analysis of a novel enzyme that catalyzes the oxidocyclization of cannabigerolic acid to cannabidiolic acid" . The Journal of Biological Chemistry . 271 (29): 17411–6. doi :10.1074/jbc.271.29.17411 . PMID 8663284 .
^ a b c d e Taura F, Sirikantaramas S, Shoyama Y, Yoshikai K, Shoyama Y, Morimoto S (June 2007). "Cannabidiolic-acid synthase, the chemotype-determining enzyme in the fiber-type Cannabis sativa" . FEBS Letters . 581 (16): 2929–34. doi :10.1016/j.febslet.2007.05.043 . PMID 17544411 .
^ Kutchan TM, Dittrich H (October 1995). "Characterization and mechanism of the berberine bridge enzyme, a covalently flavinylated oxidase of benzophenanthridine alkaloid biosynthesis in plants" . The Journal of Biological Chemistry . 270 (41): 24475–81. doi :10.1074/jbc.270.41.24475 . PMID 7592663 .
^ Carter CJ, Thornburg RW (January 2004). "Tobacco nectarin V is a flavin-containing berberine bridge enzyme-like protein with glucose oxidase activity" . Plant Physiology . 134 (1): 460–9. doi :10.1104/pp.103.027482 . PMC 316325 . PMID 14730073 .
^ "CBDAS - Cannabidiolic acid synthase precursor - Cannabis sativa (Hemp) - CBDAS gene & protein" . UniProt . Retrieved 26 February 2016 .
External links
Activity Regulation Classification Kinetics Types