BGL3 beta-glucosidase and nucleic acids encoding the same
The present invention provides a novel β-glucosidase nucleic acid sequence, designated bgl3, and the corresponding BGL3 amino acid sequence. The invention also provides expression vectors and host cells comprising a nucleic acid sequence encoding BGL3, recombinant BGL3 proteins and methods for producing the same.
1. A cell culture composition comprising a polypeptide with the biological activity of a β-glucosidase, wherein said polypeptide has an amino acid sequence of at least 95% sequence identity to the amino acid sequence of SEQ ID NO:2 and wherein said polypeptide was expressed using recombinant DNA technology.
2. A cell culture composition comprising an enzyme having β-glucosidase activity prepared by a method having the following steps;
(a) stably transforming a host cell with an expression vector comprising a polynucleotide that encodes a polypeptide having at least 95% sequence identity to the amino acid sequence of SEQ ID NO:2; and
(b) cultivating said transformed host cell under conditions suitable for said host cell to produce said polypeptide.
3. The cell culture composition of claim 1 , wherein said host cell is a filamentous fungus cell.
4. The cell culture composition of claim 3 , wherein said filamentous fungus cell is selected from the group consisting of Trichoderma, Penicillium, Humicola, Chrysosporium, Gliocladium, Aspergillus, Fusarium, Neurospora, Hypocrea , and Emericella.
5. The cell culture composition of claim 4 , wherein said filamentous fungus is Trichoderma reesei.
6. The cell culture composition of claim 4 , wherein said filamentous fungus is Aspergillus niger.
7. The cell culture composition of claim 4 , wherein said filamentous fungus is Chrysosporiurn lucknowense.
8. A method of converting a biomass to a sugar, comprising contacting said biomass with the cell culture composition of claim 1 , whereby said biomass is converted to said sugar.
9. The method of claim 8 wherein said polypeptide is in the culture medium of said cell culture.
10. The method of claim 8 , wherein said biomass is selected from the group consisting of corn stover, trees, herbaceous plants, municipal solid waste, agricultural residues, and forestry residues.
11. The method of claim 8 , wherein said conversion occurs simultaneously with fermentation of said sugar to ethanol.