A Novel Thermostable GH3 β-Glucosidase from Talaromyce leycettanus with Broad Substrate Specificity and Significant Soybean Isoflavone Glycosides-Hydrolyzing Capability
Table 2
The substrate specificity of the purified recombinant Bgl3B.
Substrate
Glycosyl linkage
Specific activity (U/mg)
Relative activity (%)
Aryl-glycosides
pNPG (2 mM)
β-Glucose
222.8 ± 6.7
100.0
Genistin (1%)
β-Glucose
69.7 ± 0.2
31.3
Daidzin (1%)
β-Glucose
50.9 ± 0.2
22.8
Amygdalin (1%)
-
146.9 ± 0.1
65.9
Oligosaccharides
Cellobiose (4 mM)
β-1,4-Glucose
189.5 ± 1.8
100.0
Cellotriose (1%)
β-1,4-Glucose
185.0 ± 4.1
97.6
Cellotetraose (1%)
β-1,4-Glucose
94.1 ± 2.1
49.7
Cellopentaose (1%)
β-1,4-Glucose
85.8 ± 1.5
45.3
Laminaritetraose (5 mM)
[β-D-Glc-1,3)]3-D-Glc
173.0 ± 4.1
91.3
Polysaccharides
Laminarin (1%)
β-1,3-Glucan
25.7 ± 0.9
100.0
Lichenan (0.5%)
1,3:(1,4)2-β-D-Glucan
25.6 ± 0.6
99.8
Barley β-D-glucan (1%)
1,3:1,4-β-D-Glucan
7.2 ± 0.2
28.1
Avicel (1%)
β-1,4-Glucose
6.6 ± 0.2
25.5
Xylan (1%)
β-1,4-Xylose
4.1 ± 0.5
16.1
CMC-Na (1%)
β-1,4-Glucose
5.9 ± 0.4
23.0
The data are shown as mean ± SD (n = 3). The specific activities of Bgl3B towards pNPG, cellobiose, and laminarin are defined as 100% for the aryl-glycosides, oligosaccharides, and polysaccharides, respectively.
