Table 2.
Enzymatic analysis of GAX oligosaccharides
| Oligosaccharide | Unknown structure | GH10 product | GH11 product | Enzyme sensitivity | ||||
|---|---|---|---|---|---|---|---|---|
| CgGH3 xylosidase | PcGH51 α-arabinosidase | PaGH62 α-arabinosidase | CjGH67 α-glucuronidase | BoGH115 α-glucuronidase | ||||
| U(4Me)2X | N1 | ●● | ● | − | − | − | − | + |
| U2XX | N2 | ● | − | − | − | + | + | |
| U(4Me)2XX | N3 | ●● | ● | − | − | − | + | + |
| A3X | N4 | ●● | − | + | + | NT | − | |
| XU 2 XX | − | ● | − | − | − | + | + | |
| XU (4Me)2 XX | − | ● | − | − | − | + | + | |
| XA3X | N5 | ●● | ●● | NT | + | + | NT | − |
| A3A3X | N6 (Z1) | ● | NT | + | − | NT | − | |
| A3XXX | N7 (Z2) | ● | NT | + | + | NT | NT | |
| XA 3 XX | − | ●● | − | NT | + | NT | − | |
| D2,3XX | N8 (Z3) | ● | + | − | − | NT | − | |
| XA3A3X | N9 | ● | − | + | − | NT | NT | |
| A3U(4Me)2XX | N10 | ● | NT | + | − | NT | − | |
| B2,3U(4Me)2XX or D2,3U(4Me)2XX |
N11 | ● | − | − | NT | NT | − | |
| XA3XU(4Me)2XX | N12 | ● | NT | + | + | NT | + | |
| D2,3X | M1 | ● | + | − | − | NT | − | |
| XD2,3XX | M2 | ● | + | − | − | NT | − | |
The dots indicate, which xylanase produces the oligosaccharide; one dot (●) indicates minor products while two dots (●●) indicate major products. Oligosaccharides sensitive to GH enzymes are marked with a plus (+), those resistant with a minus (−); NT not tested. Oligosaccharides XU2XX, X(4Me)2XX and XA3XX have been previously structurally characterised [27–29]