Fig. 3: Phylogenetic relationship of R. serpentina VR(CAD2) and DHVR(RR4) with other MIA imine/iminium reductases and alcohol dehydrogenases.

The enzymes labeled in magenta were investigated in this study. CAD cinnamyl alcohol dehydrogenase, VR vomilenine 1,2(R)-reductase, DHVR 1,2-dihydrovomilenine 19,20(S)-reductase, GS geissoschizine synthase, HYS heteroyohimbine synthase, THAS tetrahydroalstonine synthase, DCS dihydrodemethylcorynantheine/demethylcorynantheidine synthase, DPAS dihydroprecondylocarpine acetate synthase, Redox1 oxidized geissoschizine oxidoreductase 1, WS Wieland–Gumlich aldehyde synthase, T3R tabersonine 3-reductase. The plant species include: Cr Catharanthus roseus, Rs Rauvolfia serpentina, Rt Rauvolfia tetraphylla, Ms Mitragyna speciosa, Mp Mitragyna parvifolia, Co Cephalanthus occidentalis, Cp Cinchona pubescens, Vm Vinca minor, Te Tabernaemontana elegans, Sn Strychnos nux-vomica, Pt Populus tremuloides, Os Oryza sativa. The amino acid sequences and Genbank accession numbers are included in Supplementary Data 2. Evolutionary analyses were conducted in MEGA11. The evolutionary history was inferred by using the Maximum Likelihood method and JTT matrix-based model. The percentage of trees in which the associated taxa clustered together is shown next to the branches (100 bootstrap replicates). Initial tree(s) for the heuristic search were obtained automatically by applying Neighbor-Join and BioNJ algorithms to a matrix of pairwise distances estimated using the JTT model, and then selecting the topology with superior log likelihood value. The tree is drawn to scale, with branch lengths measured in the number of substitutions per site (scale bar).