Table 3 Substrate specificity for oligosaccharides of α-glucosidase TtAG, AglHHB27, AglHHB8 and TcaAG from Thermus strains
Substrate | Glycosidic linkage | Relative activity (%) | |||
|---|---|---|---|---|---|
TtAG | AglHHB27 | AglHHB8 | TcaAG | ||
Sucrose | Glu-α-1,2-Fru | 47.8 (46.1) | 12.5 (8.0) | 8.4 | 59.3 |
Trehalose | Glu-α-1,1-Glu | 103.7 (100.0) | 156.7 (100.0) | 0.0 | 0.0 |
Isomaltose | Glu-α-1,6-Glu | 100.0 (96.5) | 100.0 (63.8) | 100.0 | 100.0 |
Cellobiose | Glu-β-1,4-Glu | 0.0 | 0.0 | 0.0 | 0.0 |
Melibiose | Gla-α-1,6-Glu | 0.0 | 0.0 | 0.0 | 0.0 |
Maltose | Glu-α-1,4-Glu | 3.7 (3.5) | 15.1 (9.7) | 2.8 | 1.6 |
Melizitose | Glu-[α-1,3]-Fru-β-2,1-Glu | 0.0 | 0.0 | 0.0 | 0.0 |
Isomaltotriose | Glu-[α-1,6]-Glu-α-1,6-Glu | 188.2 (181.6) | 47.8 (30.5) | 45.2 | 4.8 |
Raffinose | Gla-[α-1,6]-Glu-α-1,2-Glu | 0.0 | 0.0 | 0.0 | 0.0 |
Panose | Glu-[α-1,6]-Glu-α-1,4-Glu | 62.5 (60.3) | 56.1 (35.8) | 42.1 | 44.6 |