Figure 5: (a) CID MS/MS of the fucosylated glycopeptide (SN(+GlcNAc- Fuc)ATTDEHGLVQF) at m/z 884.6. The major fragment at m/z 811.6 is the product ion after neutral loss of fucose from the precursor ion. Minimal peptide backbone fragmentation was observed. (b) CID MS3 of m/z 811.6 from (a) showed extensive fragmentation along the peptide backbone, providing both peptide sequence information and the glycosylation site. (c) CID MS/MS of the non-fucosylated glycopeptide (SN(+GlcNAc)ATTDEHGLVQF) at m/z 811.6. (c) has great similarity with (b), revealing presence of both fucosylation and nonfucosylation at the same site.