Iridotrial was previously proposed as an intermediate of the secologanin pathway. Whereas we never detected iridotrial as an intermediate in the iridodial to 7-deoxyloganetic acid conversion under conditions more likely to capture early reaction products such as low substrate concentrations, short incubations or low temperature, the latter was very efficiently converted into 7-deoxyloganetic acid with a Kmapp of 25 mM and kcat of 5.2 s1 (Supplementary Fig. 3). This suggests that CYP76A26 is a multifunctional P450 enzyme catalysing successive hydroxylation/dehydration steps via a mechanism
similar to that recently described for CYP701A3, which catalyses the conversion of kaurene to kaurenoic acid in the biosynthesis of gibberellins