Table 1.
MALDI-TOF analysis of N-glycans [M+Na+] from xylGalT12 leaf proteins treated with β-1,4-galactosidase (+β-galase) or left untreated (−β-galase)
| Observed m/z | Composition | Proposed structure | −β-galase | +β-galase |
|---|---|---|---|---|
| 933.3 | H3N2 | Man3GlcNAc2 | 2.6 | 2.2 |
| 1,079.3 | H3N2F1 | Man3(Fuc)GlcNAc2 | 2.5 | 2.9 |
| 1,095.3 | H4N2 | Man4GlcNAc2 | 4.2 | 4.1 |
| 1,136.3 | H3N3 | GlcNAcMan3GlcNAc2 | 1.6 | 2.2 |
| 1,241.4 | H4N2F1 | Man4(Fuc)GlcNAc2 | 1.7 | 1.7 |
| 1,257.4 | H5N2 | Man5GlcNAc2 | 16.6 | 17.0 |
| 1,298.4 | H4N3 | GlcNAcMan4GlcNAc2 | 3.2 | 4.2 |
| 1,403.4 | H5N2F1 | Man5(Fuc)GlcNAc2 | 4.1 | 4.2 |
| 1,419.4 | H6N2 | Man6GlcNAc2 | 5.0 | 5.0 |
| 1,460.4 | H5N3 | GlcNAcMan5GlcNAc2 | 14.7 | 28.1 |
| 1,581.5 | H7N2 | Man7GlcNAc2 | 4.9 | 4.5 |
| 1,606.5 | H5N3F1 | GlcNAcMan5(Fuc)GlcNAc2 | 3.3 | 4.6 |
| 1,622.5 | H6N3 | GalGlcNAcMan5GlcNAc2 | 12.5 | 0.3 |
| 1,743.5 | H8N2 | Man8GlcNAc2 | 5.4 | 5.4 |
| 1,768.6 | H6N3F1 | GalGlcNAcMan5(Fuc)GlcNAc2 | 1.9 | 0.2 |
| 1,905.6 | H9N2 | Man9GlcNAc2 | 2.5 | 2.3 |
| Total | 86.7 | 88.9 |
Values indicate percentage of total peak area. N-glycans representing <1.5% of total peak area in untreated samples have been omitted. F, fucose; H, hexose; N, N-acetylglucosamine.