Figure 3.

HCD MS/MS of an O-fucosylated and C-mannosylated glycopeptide from TSR4 of MIC2. HCD MS/MS spectrum was obtained with a collision energy of 20 eV. Detection of the Hex in the y-series ions only from y13 onward, both on singly and doubly charged species, confirms positioning of the Hex on the Trp in the WXXC motif, consistent with C-mannosylation. The y7 + dHexHex ion supports the presence of the disaccharide on Ser-485, the predicted POFUT2 site. Red triangle, fucose; green circle, mannose; white circle, Hex; *, cysteine carbamidomethylation.