Figure 3.

Comparative analysis of intact N-glycopeptides from wild type and IM_Xylt1A. An increased N-glycan trimming and decreased number of Pent in comparison to the wild type could be observed for IM_XylT1A using IS-CID. Representative MS1 spectra for ENSNTTEDGNLFGAAPNVFISR are shown for the wild type (A) and IM_XylT1A (B), respectively. Annotated ions have a charge state of two. For all identified N-glycan compositions, the number of N-glycosites harboring this glycan is shown for the wild type (gray) and IM_Xylt1A (orange; C). The N-glycan complexity is increasing from left (oligomannosidic, not methylated) to right (decorated, methylated) and N-glycan compositions have been grouped according to the presence of Pent and/or dHex (optional for sugars written in parenthesis). Only N-glycosites that have been identified in both strains were compared (n = 33). A comparison for all identified N-glycopeptides can be found in Supplemental Figure S4. Peptide sequences and their corresponding N-glycan compositions are listed in Supplemental Data S2.