title: Cloning and functional expression of thermostable beta-glucosidase gene from Thermoascus aurantiacus.
abstract: A thermostable beta-glucosidase (BGLI) was purified from Thermoascus aurantiacus IFO9748, and the gene (bgl1) encoding this enzyme was cloned and expressed in yeast Pichia pastoris. The deduced amino acid sequence encoded by bgl1 showed high similarity with the sequence of glycoside hydrolase family 3. The recombinant enzyme was purified and subjected to enzymatic characterization. Recombinant BGLI retained more than 70% of its initial activity after 1 h of incubation at 60 degrees C and was stable in the pH range 3-8. The optimal temperature for enzyme activity was about 70 degrees C and the optimal pH was about 5. P. pastoris expressing recombinant BGLI became able to utilize cellobiose as a carbon source.
authors.affiliation: Laboratory of Applied Microbiology, Research Institute of Bioresources and Biotechnology, Ishikawa Prefectural University, Nonoichi-cho, Ishikawa, 921-8836, Japan.
authors.forename: Jiong
authors.initials: J
authors.lastname: Hong
authors.forename: Hisanori
authors.initials: H
authors.lastname: Tamaki
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Kumagai
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000201:enzymology* / Q000235:genetics*; D002475:Cellobiose / Q000378:metabolism; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013696:Temperature; D001617:beta-Glucosidase / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D011994:Recombinant Proteins; D002475:Cellobiose; D001617:beta-Glucosidase