IUBMB Enzyme Nomenclature


Accepted name: tetrahydrocannabinolic acid synthase

Reaction: cannabigerolate + O2 = Δ9-tetrahydrocannabinolate + H2O2

For diagram of reaction click here.

Glossary: Δ9-tetrahydrocannabinolate = Δ9-THCA = (6aR,10aR)-1-hydroxy-6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromene-2-carboxylate
cannabigerolate = CBGA = 3-[(2E)-3,7-dimethylocta-2,6-dien-1-yl]-2,4-dihydroxy-6-pentylbenzoate
cannabinerolate = 3-[(2Z)-3,7-dimethylocta-2,6-dien-1-yl]-2,4-dihydroxy-6-pentylbenzoate

Other name(s): THCA synthase; Δ1-tetrahydrocannabinolic acid synthase

Systematic name: cannabigerolate:oxygen oxidoreductase (cyclizing, Δ9-tetrahydrocannabinolate-forming)

Comments: A flavoprotein (FAD). The cofactor is covalently bound. Part of the cannabinoids biosynthetic pathway in the plant Cannabis sativa. The enzyme can also convert cannabinerolate (the (Z)-isomer of cannabigerolate) to Δ9-THCA with lower efficiency. The traditional numbering called Δ9-tetrahydrocannabinolate, Δ1-tetrahydrocannabinolate. Systematic peripheral numbering is now recommended.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:


1. Taura, F., Morimoto, S. Shoyama, Y. and Mechoulam, R. First direct evidence for the mechanism of Δ1-tetrahydrocannabinolic acid biosynthesis. J. Am. Chem. Soc. 117 (1995) 9766-9767.

2. Sirikantaramas, S., Morimoto, S., Shoyama, Y., Ishikawa, Y., Wada, Y., Shoyama, Y. and Taura, F. The gene controlling marijuana psychoactivity: molecular cloning and heterologous expression of Δ1-tetrahydrocannabinolic acid synthase from Cannabis sativa L. J. Biol. Chem. 279 (2004) 39767-39774. [PMID: 15190053]

3. Shoyama, Y., Takeuchi, A., Taura, F., Tamada, T., Adachi, M., Kuroki, R., Shoyama, Y. and Morimoto, S. Crystallization of Δ1-tetrahydrocannabinolic acid (THCA) synthase from Cannabis sativa. Acta Crystallogr. Sect. F Struct. Biol. Cryst. Commun. 61 (2005) 799-801. [PMID: 16511162]

4. Shoyama, Y., Tamada, T., Kurihara, K., Takeuchi, A., Taura, F., Arai, S., Blaber, M., Shoyama, Y., Morimoto, S. and Kuroki, R. Structure and function of 1-tetrahydrocannabinolic acid (THCA) synthase, the enzyme controlling the psychoactivity of Cannabis sativa. J. Mol. Biol. (2012) . [PMID: 22766313]

[EC created 2012]

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