Fig. 5.

N-Glycan structure and core fucose linkage assignment of GlcNAc₂Man₅Fuc₂ (983²⁺) from NF299. The MS³ profile of the 1272 B-type ion from the difucosylated precursor illustrates that fucosylation is at the non-reducing-end GlcNAc of the chitobiose core and not at the antenna. The MS⁴ spectrum of the 646 ion (983²⁺ → 1272 → 646) shows that the topology is Hex-Fuc-GlcNAc and the fragmentation assignment is consistent with a 1-4 linkage.