IUBMB Enzyme Nomenclature


Accepted name: protostadienol synthase

Reaction: (3S)-2,3-epoxy-2,3-dihydrosqualene = (17Z)-protosta-17(20),24-dien-3β-ol

For reaction pathway click here.

Other name(s): PdsA; (S)-2,3-epoxysqualene mutase [cyclizing, (17Z)-protosta-17(20),24-dien-3β-ol-forming]

Systematic name: (3S)-2,3-epoxy-2,3-dihydrosqualene mutase [cyclizing, (17Z)-protosta-17(20),24-dien-3β-ol-forming]

Comments: (17Z)-Protosta-17(20),24-dien-3β-ol is a precursor of the steroidal antibiotic helvolic acid.

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


1. Lodeiro, S., Xiong, Q., Wilson, W.K., Ivanova, Y., Smith, M.L., May, G.S. and Matsuda, S.P. Protostadienol biosynthesis and metabolism in the pathogenic fungus Aspergillus fumigatus. Org Lett 11 (2009) 1241-1244. [PMID: 19216560]

[EC created 2011]

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