CA2240390A1

CA2240390A1 - Novel xylanases, genes encoding them, and uses thereof

Info

Publication number: CA2240390A1
Application number: CA002240390A
Authority: CA
Inventors: Marja Paloheimo; Satu Hakola; Arja Mantyla; Jari Vehmaanpera; Raija Lantto; Tarja Lahtinen; Richard Fagerstrom; Pirkko Suominen
Original assignee: Individual
Current assignee: AB Enzymes Oy
Priority date: 1995-12-18
Filing date: 1996-12-17
Publication date: 1997-06-26
Anticipated expiration: 2016-12-17
Also published as: CA2240390C

Abstract

DNA encoding novel xylanases, vectors containing such DNA, hosts transformed with such DNA, enzyme preparations, and the use of such preparations are described.

Claims

1. A nucleic acid molecule encoding a polypeptide having the enzymatic activity of xylanase, selected from the group consisting of:
(a) nucleic acid molecules encoding a polypeptide comprising the amino acid sequence as depicted in Figure 2, 3 or 4;
(b) nucleic acid molecules comprising the coding sequence of the nucleotide sequence as depicted in Figure 2, 3 or 4;
(c) nucleic acid molecules encoding a polypeptide comprising the amino acid sequence encoded by the DNA insert contained in DSM 11021, DSM 11022 or DSM 11023;
(d) nucleic acid molecules comprising the coding sequence of the DNA insert contained in DSM 11021, DSM 11022 or DSM 11023;
(e) nucleic acid molecules the coding sequence of which differs from the coding sequence of a nucleic acid molecule of any one of (a) to (d) due to the degeneracy of the genetic code; and (f) nucleic acid molecules hybridizing to a molecule of any one of (a) - (d), and encoding a polypeptide having xylanase activity and having an amino acid sequence which shows at least 80 % identity to a sequence as depicted in Figure 2,3 or 4

2. The nucleic acid molecule of claim 1 encoding a polypeptide having a temperature optimum of over 50 °C.

3. The nucleic acid molecule according to claims 1 and 2 encoding a polypeptide having a temperature optimum of over 50 °C at pH 4 to 8.

4. The nucleic acid molecule according to claims 1 to 3 encoding a polypeptide having a temperature of over 50 °C at pH 5 to 7.

5. The nucleic acid molecule of claim 1 which is RNA.

6. The nucleic acid molecule of claim 1 which is DNA.

7. The DNA of claim 4 which is genomic DNA or cDNA.

8. A vector containing a nucleic acid molecule of any one of claims 1 to 7.

9. The vector of claim 8, in which the nucleic acid molecule is operably linked to expression control sequences allowing expression in prokaryotic or eukaryotic host cells.

10. A host cell transformed with a nucleic acid molecule of any one of claims 1 to 7 or with a vector of claim 8 or 9.

11. The host cell of claim 10 which belongs to filamentous fungi.

12. The host cell of claims 10 to 11 which belongs to the genus Trichoderma or Aspergillus.

13. The host cell of claim 12 which is Trichoderma reesei.

14. A process for the production of a polypeptide having xylanase activity comprising the steps of culturing the host cell of any one of claims 10 to 13 and recovering the polypeptide from the culture medium.

15. A polypeptide having xylanase activity encoded by a nucleic acid molecule of any one of claims 1 to 7, a vector of claim 8 or 9 and obtainable by the process of claim 14.

16. A process for the preparation of an enzyme preparation comprising a polypeptide of claim 15 comprising the steps of culturing a host cell of any one of claims 10 to 13 and either recovering the polypeptide from the cells or separating the cells from the culture medium and obtaining the supernatant.

17. An enzyme preparation obtainable by the process of claim 16.

18. The enzyme preparation of claim 17, which is liquid.

19. The enzyme preparation of claim 17, which is dry.

20. The enzyme preparation of claim 17, wherein said supernatant has been concentrated.

21. A method of treating wood-derived pulp or fiber, comprising the step of adding an enzyme preparation of any one of claims 17 to 20 to wood-derived mechanical or chemical pulp or secondary fiber.

22. A method of bleaching pulp, comprising the step of contacting said pulp with an enzyme preparation of any one of claims 17 to 20.

23. A method of improving the quality of animal feed, which comprises treating plant material with an enzyme preparation of any one of claims 17 to 20.

24. A method for baking, which comprises adding an enzyme preparation of any one of claims 17 to 20 to flour used in preparation of dough.

25. Use of an enzyme preparation according to any one of claims 17 to 20 in the degradation of xylan-containing substrate.

26. Use of an enzyme preparation according to any one of claims 17 to 20 in the preparation of animal feedstuff.

27. An animal feedstuff composition comprising an enzyme preparation according to any one of claims 17 to 20.

28. Use of an enzyme preparation according to any one of claims 17 to 20 in a dough for the preparation of breads.

29. A flour composition comprising an enzyme preparation according to any one of claims 17 to 20.

30. A doug composition comprising an enzyme preparation according to any one of claims 17 to 20 as bread improving component.

31. Use of an enzyme preparation according to any one of claims 17 to 20 in the production of wood pulp.

32. Use of an enzyme preparation according to any one of claims 17 to 20 in bleaching of wood pulp.

33. Use of an enzyme preparation according to any one of claims 17 to 20 and of claim 29 in bleaching of chemical or mechanical wood pulp.

34. Use of an enzyme preparation according to any one of claims 17 to 20 for treating wood-derived pulp.

35. Use of an enzyme preparation according to any one of claims 17 to 20 and of claim 31 for treating chemical, mechanical or secondary fibers.