Fig. 3: Discovery of C. ipecacuanha and A. salviifolium protoemetine biosynthetic genes.
From: Ipecac alkaloid biosynthesis in two evolutionarily distant plants
a, The complete pathway leading to protoemetine (8). Molecules in parentheses are hypothesized unstable intermediates that were not detected by LC–MS. Aldehydes 7 and 8 were only detected in traces by LC–MS; instead, the corresponding alcohols 9 and 10 were detected. Peak identities were confirmed by comparing to standards (full MS characterization in Supplementary Figs. 5 and 7; NMR characterization of protoemetine standard in Supplementary Fig. 26), except 10-O-demethylprotoemetinol, which was identified on the basis of MS2 fragmentation (Supplementary Fig. 11). Spont., spontaenous. b, LC–MS peak areas of products in N. benthamiana upon expression of indicated C. ipecacuanha pathway genes and infiltration of a synthetically generated mixture of DAII (4a) and DAI (4b). Data are the mean ± s.e.m. of n = 3 biological replicates; dots are single data points. c, LC–MS peak areas of products in N. benthamiana upon expression of indicated A. salviifolium pathway genes and infiltration of synthetically generated mixture of DAIIA (5a) and DAIA (5b). Data are the mean ± s.e.m. of n = 3 biological replicates; dots are single data points. d, The EIC for protoemetinol upon expression of indicated C. ipecacuanha pathway genes (blue) or A. salviifolium pathway genes (magenta) and authentic standard (black). e, MS2 fragmentation for the corresponding peaks shown in d, confirming the peak as protoemetinol. Synthesis of the protoemetinol standard is described in the Supplementary Methods. Results of additional gene combinations are shown in Extended Data Figs. 4 and 6.
