Cloning, expression and characterization of beta-glucosidase from Aspergillus fumigatus.
- Author:
Yi XIE
1
;
Haomiao OUYANG
1
;
Ribo HUANG
2
;
Dong CHEN
2
;
Cheng JIN
1
Author Information
1. State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
2. Guangxi Key Laboratory of Biorefinery, State Key Laboratory of Non-Food Biomass and Enzyme Technology, National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Science, Nanning 530007, Guangxi, China.
- Publication Type:Journal Article
- MeSH:
Aspergillus fumigatus;
enzymology;
Cloning, Molecular;
Enzyme Stability;
Escherichia coli;
genetics;
metabolism;
Recombinant Proteins;
biosynthesis;
genetics;
metabolism;
beta-Glucosidase;
biosynthesis;
genetics;
metabolism
- From:
Chinese Journal of Biotechnology
2013;29(9):1245-1253
- CountryChina
- Language:Chinese
-
Abstract:
Exploring new beta-glucosidase genes is of great importance to industrialize beta-glucosidase. The genomes of Aspergillus fumigatus contain a bgl gene, which encodes a 65 kDa putative beta-glucosidase. The bgl gene was cloned into an expression plasmid and transformed to Escherichia coli BL21 (DE3). The bgl was expressed upon induction of Isopropyl beta-D-1-thiogalactopyranoside (IPTG). The recombinant protein was purified by GST-tag affinity chromatography. The purified recombinant Bgl was characterized using Esculin as substrate. The optimum temperature and pH were 45 degrees C and 5.0-6.0, respectively. The K(m) for Esculin was 17.7 mmol/L. The enzyme was stable in the range of pH 4-7. After incubation at 70 degrees C for 2 h, the recombinant Bgl remained 60% of its activity. Metal ions and chemical reagents had different influences on the activity of beta-glucosidase. Ca2+ (1 mmol/L) could increase enzyme activity slightly. On the contrary, the enzyme activity was greatly inhibited by 5 mmol/L Sodium dodecyl sulfate (SDS). Based on our results, the A. fumigatus Bgl was thermostable beta-glucosidase.
