Fig. 4: Glycan composition fragment counting approximation.

The number of distinct mass fragments produced by fragmenting a known topology of N-glycan of a given size, enclosed by our two approximation proposals, with and without the presence of core fucosylation. Each labeled vertical line denotes a class of complex-type N-glycan of ascending number of lactosamine units beyond the core motif, which are arranged as separate branches. The immature high mannose from Man9 to Man4 are also shown, which fall below the approximation due to the homogeneity of their Y fragments.