IUBMB Enzyme Nomenclature


Accepted name: β-seco-amyrin synthase

Reaction: (3S)-2,3-epoxy-2,3-dihydrosqualene = β-seco-amyrin

For diagram of reaction click here.

Glossary: β-seco-amyrin = 8,14-secooleana-7,13-diene-3β-ol

Systematic name: (3S)-2,3-epoxy-2,3-dihydrosqualene mutase (cyclizing, β-seco-amyrin-forming)

Comments: The enzyme from Arabidopsis thaliana is multifunctional and produces about equal amounts of α- and β-seco-amyrin. See EC, α-seco-amyrin synthase.

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


1. Shibuya, M., Xiang, T., Katsube, Y., Otsuka, M., Zhang, H. and Ebizuka, Y. Origin of structural diversity in natural triterpenes: direct synthesis of seco-triterpene skeletons by oxidosqualene cyclase. J. Am. Chem. Soc. 129 (2007) 1450-1455. [PMID: 17263431]

[EC created 2011]

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