IUBMB Enzyme Nomenclature


Accepted name: iridoid synthase

Reaction: (6E)-8-oxogeranial + NAD(P)H + H+ = cis-trans-nepetalactol + NAD(P)+

For diagram of reaction click here.

Glossary: cis-trans-nepetalactol = (4aS,7S,7aR)-4,7-dimethyl-1,4a,5,6,7,7a-hexahydrocyclopenta[c]pyran-1-ol

Systematic name: 8-oxogeranial:NAD(P)+ oxidoreductase (cyclizing, cis-trans-nepetalactol forming)

Comments: Isolated from the plant Catharanthus roseus. The reaction may involve cyclization via a Diels-Alder or Michael reaction. Iridoids are involved in the biosynthesis of many indole alkaloids. The cyclic hemiacetal is readily hydrolysed to the corresponding dial.

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


1. Geu-Flores, F., Sherden, N.H., Courdavault, V., Burlat, V., Glenn, W.S., Wu, C., Nims, E., Cui, Y. and O'Connor, S.E. An alternative route to cyclic terpenes by reductive cyclization in iridoid biosynthesis. Nature 492 (2012) 138-142. [PMID: 23172143]

[EC created 2013]

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