Polypeptides having xylanase activity and polynucleotides encoding same

1. An isolated polypeptide having xylanase activity, selected from the group consisting of:

(a) a polypeptide having at least 95% sequence identity to the mature polypeptide of SEQ ID NO: 2;

(b) a polypeptide encoded by a polynucleotide that hybridizes under very high stringency conditions with (i) the mature polypeptide coding sequence of SEQ ID NO: 1, (ii) the cDNA sequence contained in the mature polypeptide coding sequence of SEQ ID NO: 1, or (iii) the full-length complementary strand of (i) or (ii); and

(c) a polypeptide encoded by a polynucleotide having at least 95% sequence identity to the mature polypeptide coding sequence of SEQ ID NO: 1 or the cDNA sequence thereof.

2. The polypeptide of claim 1 , which is encoded by the polynucleotide contained in plasmid pMMar26 which is contained in E. coli NRRL B-50266.

3. An isolated polynucleotide encoding the polypeptide of claim 1 .

4. A recombinant host cell comprising the polynucleotide of claim 3 operably linked to one or more control sequences that direct the production of the polypeptide.

5. A method of producing the polypeptide of claim 1 , comprising:

(a) cultivating a cell, which in its wild-type form produces the polypeptide, under conditions conducive for production of the polypeptide; and

(b) recovering the polypeptide.

6. A method of producing the polypeptide of claim 1 , comprising:

(a) cultivating a host cell comprising a polynucleotide encoding the polypeptide operably linked to one or more control sequences that direct the production of the polypeptide under conditions conducive for production of the polypeptide; and

(b) recovering the polypeptide.

7. A transgenic plant, plant part or plant cell transformed with a polynucleotide encoding the polypeptide of claim 1 .

8. A method of producing a polypeptide having xylanase activity, comprising:

(a) cultivating the transgenic plant or the plant cell of claim 7 under conditions conducive for production of the polypeptide; and

(b) recovering the polypeptide.

9. A method of producing a mutant of a parent cell, comprising inactivating a polynucleotide encoding the polypeptide of claim 1 , which results in the mutant producing less of the polypeptide than the parent cell.

10. A double-stranded inhibitory RNA (dsRNA) molecule comprising a subsequence of the polynucleotide of claim 3 , wherein optionally the dsRNA is an siRNA or an miRNA molecule.

11. A method of inhibiting the expression of a polypeptide having xylanase activity in a cell, comprising administering to the cell or expressing in the cell a double-stranded RNA (dsRNA) molecule, wherein the dsRNA comprises a subsequence of the polynucleotide of claim 3 .

12. An isolated polynucleotide encoding a signal peptide comprising or consisting of amino acids 1 to 23 of SEQ ID NO: 2.

13. A recombinant host cell comprising the polynucleotide of claim 12 , operably linked to a gene encoding a protein, wherein the gene is foreign to the polynucleotide encoding the signal peptide.

14. A method of producing a protein, comprising:

(a) cultivating the recombinant host cell of claim 13 under conditions conducive for production of the protein; and

(b) recovering the protein.

15. A method for degrading or converting a cellulosic or xylan-containing material, comprising: treating the cellulosic or xylan-containing material with an enzyme composition in the presence of the polypeptide having xylanase activity of claim 1 .

16. The method of claim 15 , further comprising recovering the degraded cellulosic or xylan-containing material.

17. A method for producing a fermentation product, comprising:

(a) saccharifying a cellulosic or xylan-containing material with an enzyme composition in the presence of the polypeptide having xylanase activity of claim 1 ;

(b) fermenting the saccharified cellulosic or xylan-containing material with one or more fermenting microorganisms to produce the fermentation product; and

(c) recovering the fermentation product from the fermentation.

18. A method of fermenting a cellulosic or xylan-containing material, comprising: fermenting the cellulosic or xylan-containing material with one or more fermenting microorganisms, wherein the cellulosic or xylan-containing material is saccharified with an enzyme composition in the presence of the polypeptide having xylanase activity of claim 1 .

19. The method of claim 18 , wherein the fermenting of the cellulosic or xylan-containing material produces a fermentation product.

20. The method of claim 19 , further comprising recovering the fermentation product from the fermentation.

21. The polypeptide of claim 1 , having at least 97% sequence identity to the mature polypeptide of SEQ ID NO: 2.

22. The polypeptide of claim 1 , having at least 98% sequence identity to the mature polypeptide of SEQ ID NO: 2.

23. The polypeptide of claim 1 , having at least 99% sequence identity to the mature polypeptide of SEQ ID NO: 2.

24. The polypeptide of claim 1 , comprising or consisting of SEQ ID NO: 2.

25. The polypeptide of claim 1 , comprising or consisting of the mature polypeptide of SEQ ID NO: 2.

26. The polypeptide of claim 25 , wherein the mature polypeptide is amino acids 24 to 403 of SEQ ID NO: 2.

27. The polypeptide of claim 1 , which is encoded by a polynucleotide having at least 97% sequence identity to the mature polypeptide coding sequence of SEQ ID NO: 1 or the cDNA sequence thereof.

28. The polypeptide of claim 1 , which is encoded by a polynucleotide having at least 98% sequence identity to the mature polypeptide coding sequence of SEQ ID NO: 1 or the cDNA sequence thereof.

29. The polypeptide of claim 1 , which is encoded by a polynucleotide having at least 99% sequence identity to the mature polypeptide coding sequence of SEQ ID NO: 1 or the cDNA sequence thereof.