Fig. 3.

Separation of UDP and six UDP-sugars at the beginning (a), after 60 h (approx. 25 runs) of a measurement sequence (b), and (c) in a real sample extracted from Arabidopsis leaves. Chromatographic conditions are given in the materials and methods section; sample, 1.0 μmol L⁻¹ each compound, 2.65 μL injected; extracted ion current chromatograms (EICC) were obtained from the raw data at the respective monoisotopic masses of the deprotonated UDP-sugars (402.9949 Da for UDP, 535.0371 Da for UDP-Xyl and UDP-Ara, 565.0477 Da for UDP-Gal and UDP-Glc, 579.0270 Da for UDP-GalA and UDP-GlcA) with a mass window of 10 ppm and five-point Gaussian smoothing. Pairs of isobaric UDP-sugars are labeled with asterisks