Fig. 5: In vitro enzymatic cascade with labelled nicotinic acid.
From: Nicotine biosynthesis is completed by cryptic activating glucosylation
A Schematic of reaction cascade with nicotinic acid-(ring-d4) (2-d4). B Selected in vitro cascades with 2-d4 substrate. Bar charts show EIC peak areas of product (from L-to-R: 10, 12, 13, 1) isotopologues (all m/z ± 0.15 except for d3-12 which was m/z ± 0.5 due to peak shape distortion). Reactions performed in triplicate, bars show mean peak area, points show individual measurements, and error bars show standard deviation. Each row corresponds to an in vitro reaction, with the matrix showing presence/absence (blue/white) of reaction components. Letters above bars are significant groupings of d3/d4 isotopologue ratios, determined per chemical across all reaction combinations (p < 0.05, Tukey’s HSD test, Supplementary Data 6, see Supplementary Fig. 8 for all reactions). C–E Conversion of nicotinic acid (2) isotopologues by the nicotine biosynthetic cascade (NaGT, NaGR, NicGH, NADPH and UDP-Glc) with and without NicGS. Bar charts show peak areas of products from EICs. Reactions were performed in triplicate (points); bars show mean peak area; error bars show standard deviation. Source data are provided as a Source Data file.
