Extended Data Fig. 1: Characterization of GsOMT1.
From: Discovery and engineering of colchicine alkaloid biosynthesis
a, LC–MS chromatograms demonstrating activity on substrate 1 by protein lysates from N. benthamiana leaves that transiently express GsOMT1. EICs for 1 (m/z 286.1438; left) and the methylated product (indicated by the asterisk) produced in this experiment (m/z 300.1594; right) are shown. This experiment was performed three times, with similar results each time. b, MS/MS fragmentation spectrum of 1, as well as the generated m/z 300.1594 product (*) at a collision energy of 20 V. Fragmentation of both compounds was performed twice, with similar results observed each time. c, Tabulated list and putative structures for ion fragments from the MS/MS analysis of 1. d, Tabulated list and putative structures for ion fragments from the MS/MS analysis of the m/z 300.1594 product. See Supplementary Information for a detailed analysis of MS/MS results. e, Proposed reaction catalysed by GsOMT1, as supported by MS/MS fragmentation and previously published labelling studies. f, Transient expression of GsOMT1 in N. benthamiana with co-infiltrated substrate 1 results in production of the methylated product 2, as shown by the LC–MS chromatograms. This experiment was performed more than three times with similar results observed each time. g, Untargeted metabolite analysis (XCMS) comparing transient expression of GFP (negative control) to that of GsOMT1 with co-infiltrated substrate 1 (n = 3 independent replicates for each experimental condition). The unique mass signatures (P < 0.1 between samples, as determined by XCMS) are shown in ranked order based on their increasing (top) or decreasing (bottom) fold change in abundance between the two conditions. The mass isotopologues (M0 and M1) for the presumed product (m/z 300.1594) are shown in red; the substrate (1, m/z 286.1438) is shown in blue. r.t., retention time.
