Beta-glucosidase variants and polynucleotides encoding same
The present invention relates to beta-glucosidase variants, e.g. beta-glucosidase variants of a parent Family GH3A beta-glucosidase from Aspergillus fumigatus . The present invention also relates to polynucleotides encoding the beta-glucosidase variants; nucleic acid constructs, vectors, and host cells comprising the polynucleotides; and methods of using the beta-glucosidase variants.
1. A beta-glucosidase variant, comprising a substitution to a parent beta-glucosidase at one or more positions corresponding to positions selected from the group consisting of 89, 91, 100, 140, 186, 283, and 456 of SEQ ID NO: 2, wherein the variant has beta-glucosidase activity, and wherein the variant comprises an amino acid sequence having at least 95% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
2. The variant of claim 1 , which comprises one or more substitutions selected from the group consisting of L89M, G91L, F100D, I140V, I186V, S283G, and N456E.
3. The variant of claim 1 , which comprises at least one of the substitutions L89M, G91L, F100D, I140V, I186V, S283G, or N456E, wherein the variant comprises an amino acid sequence having at least 98% but less than 100% sequence identify to amino acids 20 to 863 of SEQ ID NO: 2.
4. The variant of claim 3 , wherein the variant comprises an amino acid sequence having at least 99% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
5. An isolated polynucleotide encoding the variant of claim 1 .
6. A host cell comprising an expression vector, wherein the expression vector comprises the polynucleotide of claim 5 .
7. A method of producing a variant, said method comprising:
(a) cultivating the host cell of claim 6 under conditions suitable for the expression of the variant; and
(b) recovering the variant.
8. A method for degrading a cellulosic material, said method comprising: treating the cellulosic material with an enzyme composition, wherein the composition comprises the variant of claim 1 .
9. The method of claim 8 , said method further comprising recovering the degraded cellulosic material.
10. The method of claim 8 , wherein the enzyme composition comprises one or more enzymes selected from the group consisting of a cellulase, a polypeptide having cellulolytic enhancing activity, a hemicellulase, an expansin, an esterase, a laccase, a ligninolytic enzyme, a pectinase, a peroxidase, a protease, and a swollenin.
11. A method for producing a fermentation product, said method comprising:
(a) saccharifying a cellulosic material with an enzyme composition, wherein the composition comprises the variant of claim 1 ;
(b) fermenting the saccharified cellulosic material with one or more fermenting microorganisms to produce the fermentation product; and
(c) recovering the fermentation product from the fermentation.
12. A whole broth formulation or cell culture composition comprising the variant of claim 1 .
13. The variant of claim 1 , wherein the parent beta-glucosidase comprises an amino acid sequence having at least 95% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
14. The variant of claim 1 , wherein the parent beta-glucosidase comprises an amino acid sequence having at least 97% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
15. The variant of claim 1 , wherein the parent beta-glucosidase comprises an amino acid sequence having at least 98% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
16. The variant of claim 1 , wherein the parent beta-glucosidase comprises an amino acid sequence having at least 99% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
17. The variant of claim 1 , wherein the parent beta-glucosidase comprises an amino acid sequence having amino acids 20 to 863 of SEQ ID NO: 2.
18. The variant of claim 1 , which comprises a substitution to a parent beta-glucosidase at a position corresponding to position 89 of SEQ ID NO: 2.
19. The variant of claim 18 , wherein the substitution is to Met.
20. The variant of claim 1 , which comprises a substitution to a parent beta-glucosidase at a position corresponding to position 91 of SEQ ID NO: 2.
21. The variant of claim 20 , wherein the substitution is to Leu.
22. The variant of claim 1 , which comprises a substitution to a parent beta-glucosidase at a position corresponding to position 100 of SEQ ID NO: 2.
23. The variant of claim 22 , wherein the substitution is to Asp.
24. The variant of claim 1 , which comprises a substitution to a parent beta-glucosidase at a position corresponding to position 140 of SEQ ID NO: 2.
25. The variant of claim 24 , wherein the substitution is to Val.
26. The variant of claim 1 , which comprises a substitution to a parent beta-glucosidase at a position corresponding to position 186 of SEQ ID NO: 2.
27. The variant of claim 26 , wherein the substitution is to Val.
28. The variant of claim 1 , which comprises a substitution to a parent beta-glucosidase at a position corresponding to position 283 of SEQ ID NO: 2.
29. The variant of claim 26 , wherein the substitution is to Gly.
30. The variant of claim 1 , which comprises a substitution to a parent beta-glucosidase at a position corresponding to position 456 of SEQ ID NO: 2.
31. The variant of claim 30 , wherein the substitution is to Glu.
32. The variant of claim 1 , which further comprises a substitution to a parent beta-glucosidase at a position corresponding to position 512 of SEQ ID NO: 2.
33. The variant of claim 32 , wherein the substitution is to Tyr.
34. The variant of claim 1 , which comprises a Met at a position corresponding to position 89 of SEQ ID NO: 2, a Leu at a position corresponding to position 91 of SEQ ID NO. 2, a Val at a position corresponding to position 140 of SEQ ID NO: 2, and a Val at a position corresponding to position 186 of SEQ ID NO: 2.
35. The variant of claim 1 , which comprises an Asp at a position corresponding to position 100 of SEQ ID NO: 2, a Gly at a position corresponding to position 283 of SEQ ID NO: 2, and a Glu at a position corresponding to position 456 of SEQ ID NO: 2.
36. The variant of claim 1 , wherein the variant further comprises a substitution corresponding to position 512 of SEQ ID NO: 2, wherein the variant has beta-glucosidase activity, and wherein the variant comprises an amino acid sequence having at least 98% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
37. The variant of claim 36 , wherein the variant comprises an amino acid sequence having at least 99% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
38. The variant of claim 1 , wherein the parent beta-glucosidase comprises an amino acid sequence having at least 96% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
39. The variant of claim 1 , wherein the variant comprises an amino acid sequence having at least 96% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
40. The variant of claim 1 , wherein the variant comprises an amino acid sequence having at least 97% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
41. The variant of claim 1 , wherein the variant comprises an amino acid sequence having at least 98% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
42. The variant of claim 1 , wherein the variant comprises an amino acid sequence having at least 99% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
43. A method for obtaining a variant, said method comprising introducing into a parent beta-glucosidase a substitution at one or more positions corresponding to positions 89, 91, 100, 140, 186, 283, or 456 of SEQ ID NO: 2, wherein the variant has beta-glucosidase activity, and wherein the parent beta-glucosidase comprises an, amino acid sequence having at least 98% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2; and recovering the variant.
44. The method of claim 43 , wherein the variant beta-glucosidase comprises an amino acid sequence having at least 99% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
45. A beta-glucosidase variant, comprising a substitution to a parent beta-glucosidase at one or more positions corresponding to positions 89, 91, 100, 140, 186, 283, or 456 of SEQ ID NO: 2, wherein the variant has beta-glucosidase activity, and wherein the variant comprises an amino acid sequence having at least 95% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
46. The variant of claim 45 , wherein the parent beta-glucosidase comprises an amino acid sequence having at least 99% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
47. The variant of claim 45 , wherein the parent beta-glucosidase comprises an amino acid sequence having amino acids 20 to 863 of SEQ ID NO: 2.
48. The variant of claim 45 , wherein the variant further comprises a substitution corresponding to position 512 of SEQ ID NO: 2.
49. The variant of claim 48 , wherein the substitution is to Tyr.
50. The beta-glucosidase variant of claim 45 , wherein the variant comprises an amino acid sequence having at least 96% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
51. The beta-glucosidase variant of claim 45 , wherein the variant comprises an amino acid sequence having at least 97% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.
52. The beta-glucosidase variant of claim 45 , wherein the variant comprises an amino acid sequence having at least 98% but less than 100% sequence identity to amino acids 20 to 863 of SEQ ID NO: 2.