Covalent immobilization of β-1,4-glucosidase from Agaricus arvensis onto functionalized silicon oxide nanoparticles.
An efficient β-1,4-glucosidase (BGL) secreting strain, Agaricus arvensis, was isolated and identified. The relative molecular weight of the purified A. arvensis BGL was 98 kDa, as determined by sodium dodecylsulfate polyacrylamide gel electrophoresis, or 780 kDa by size exclusion chromatography, indicating that the enzyme is an octamer. Using a crude enzyme preparation, A. arvensis BGL was covalently immobilized onto functionalized silicon oxide nanoparticles with an immobilization efficiency of 158%. The apparent V (max) (k (cat)) values of free and immobilized BGL under standard assay conditions were 3,028 U mg protein(-1) (4,945 s(-1)) and 3,347 U mg protein(-1) (5,466 s(-1)), respectively. The immobilized BGL showed a higher optimum temperature and improved thermostability as compared to the free enzyme. The half-life at 65 °C showed a 288-fold improvement over the free BGL. After 25 cycles, the immobilized enzyme still retained 95% of the original activity, thus demonstrating its prospects for commercial applications. High specific activity, high immobilization efficiency, improved stability, and reusability of A. arvensis BGL make this enzyme of potential interest in a number of industrial applications.
Singh
Raushan Kumar
RK
Department of Chemical Engineering, Konkuk University, 1 Hwayang-Dong, Gwangjin-Gu, Seoul, South Korea, 143-701.
Zhang
Ye-Wang
YW
Nguyen
Ngoc-Phuong-Thao
NP
Jeya
Marimuthu
M
Lee
Jung-Kul
JK
D000364:Agaricus / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000302:isolation & purification; D005656:Fungal Proteins / Q000737:chemistry* / Q000302:isolation & purification; D007700:Kinetics; D008970:Molecular Weight; D053758:Nanoparticles / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D012988:Soil Microbiology; D001617:beta-Glucosidase / Q000737:chemistry* / Q000302:isolation & purification
D004800:Enzymes, Immobilized; D005656:Fungal Proteins; D012822:Silicon Dioxide; D001617:beta-Glucosidase