Table 1.
Structures of GAX oligosaccharides and their migration positions by DASH expressed in glucose units (GU)
| Nomenclature | Structure | Unknown structure | MALDI-CID or NMR figure | Glucose units |
|---|---|---|---|---|
| U(4Me)2X | 4-O-Me-α-GlcpA-(1 → 2)-β-Xylp-(1 → 4)-Xylp | N1 | S3 | 0.72 |
| X | Xylp | 0.80 | ||
| U2XX | α-GlcpA-(1 → 2)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | N2 | 1.40 | |
| U(4Me)2XX | 4-O-Me-α-GlcpA-(1 → 2)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | N3 | S4 | 1.48 |
| X2 | β-Xylp-(1 → 4)-Xylp | 1.57 | ||
| XU 2 XX | β-Xylp-(1 → 4)-[α-GlcpA-(1 → 2)]-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | 2.03 | ||
| XU (4Me)2 XX | β-Xylp-(1 → 4)-[4-O-Me-α-GlcpA-(1 → 2)]-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | 2.07 | ||
| X3 | β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | 2.24 | ||
| A3X | α-Araf-(1 → 3)-β-Xylp-(1 → 4)-Xylp | N4 | S5 | 2.31 |
| A3U(4Me)2XX | α-Araf-(1 → 3)-β-Xylp-(1 → 4)-[4-O-Me-α-GlcpA-(1 → 2)]-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | N10 | S8 | 2.74 |
| XA3X | β-Xylp-(1 → 4)-[α-Araf-(1 → 3)]-β-Xylp-(1 → 4)-Xylp | N5 | S6 | 2.87 |
| B2,3U(4Me)2XX or D2,3U(4Me)2XX |
Araf-(1 → 2)-α-Araf-(1 → 3)-β-Xylp-(1 → 4)-[α-GlcpA-(1 → 2)]-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp β-Xylp-(1 → 2)-α-Araf-(1 → 3)-β-Xylp-(1 → 4)-[α-GlcpA-(1 → 2)]-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp |
N11 | S9 | 3.09 |
| D2,3X | β-Xylp-(1 → 2)-α-Araf-(1 → 3)-β-Xylp-(1 → 4)-Xylp | M1 | S12 | 3.12 |
| X4 | β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | 3.17 | ||
| A3A3X | α-Araf-(1 → 3)-β-Xylp-(1 → 4)-[α-Araf-(1 → 3)]-β-Xylp-(1 → 4)-Xylp | N6 (Z1) | 5A | 3.70 |
| A3XXX | α-Araf-(1 → 3)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | N7 (Z2) | 5B | 3.85 |
| XA 3 XX | β-Xylp-(1 → 4)-[α-Araf-(1 → 3)]-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | 3.92 | ||
| D2,3XX | β-Xylp-(1 → 2)-α-Araf-(1 → 3)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | N8 (Z3) | 5C 5D |
3.97 |
| XA3XU(4Me)2XX | β-Xylp-(1 → 4)-[α-Araf-(1 → 3)]-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-[4-O-Me-α-GlcpA-(1 → 2)]-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | N12 | S10 | 4.01 |
| X5 | β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | 4.32 | ||
| XA3A3X | β-Xylp-(1 → 4)-[α-Araf-(1 → 3)]-β-Xylp-(1 → 4)-[α-Araf-(1 → 3)]-β-Xylp-(1 → 4)-Xylp | N9 | S7 | 4.47 |
| XD2,3XX | β-Xylp-(1 → 4)-[β-Xylp-(1 → 2)-α-Araf-(1 → 3)]-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | M2 | S11 | 4.83 |
| X6 | β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-β-Xylp-(1 → 4)-Xylp | 5.54 |