Proposed structures for 20 most abundant N-glycan signals detected in the present study. Proposed structures for 20 most abundant N-glycan signals detected in the present study (13 neutral and 7 sialylated N-glycans) are based on combined results from MALDI-TOF mass spectrometry, proton NMR spectroscopy (NMR), and exoglycosidase analyses with α-mannosidase (αMan), β1,4- and β1,3-galactosidase (β4Gal), β-N-acetylglucosaminidase, specific α1,3/4- and α1,2-fucosidases (α3/4Fuc and α2Fuc), and broad-range sialidase (SA). Relative abundances in hESC and EB N-glycan profiles are indicated. Only the positive identifications in 1H-NMR analyses and sensitivity to specific exoglycosidase digestions have been marked. Monosaccharide symbols are as in Figure 1. Where appropriate, glycosidic bonds have been indicated. Two simplifying assumptions have been made: i) in structures with H ≥ 3 and N ≥ 2, the proposed structures have been assigned a trimannosyl core structure, and ii) all fucosylated structures have been assigned a core fucose residue.