IUBMB Enzyme Nomenclature


Accepted name: tirucalladienol synthase

Reaction: (3S)-2,3-epoxy-2,3-dihydrosqualene = tirucalla-7,24-dien-3β-ol

For diagram of reaction click here.

Other name(s): PEN3

Systematic name: (3S)-2,3-epoxy-2,3-dihydrosqualene mutase (cyclizing, tirucalla-7,24-dien-3β-ol-forming)

Comments: The product from Arabidopsis thaliana is 85% tirucalla-7,24-dien-3β-ol with trace amounts of other triterpenoids.

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


1. Morlacchi, P., Wilson, W.K., Xiong, Q., Bhaduri, A., Sttivend, D., Kolesnikova, M.D. and Matsuda, S.P. Product profile of PEN3: the last unexamined oxidosqualene cyclase in Arabidopsis thaliana. Org. Lett. 11 (2009) 2627-2630. [PMID: 19445469]

[EC created 2011]

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