Polypeptides having xylanase activity and polynucleotides encoding same

A nucleic acid construct or recombinant expression vector comprising an isolated polynucleotide encoding a polypeptide having xylanase activity, wherein the polynucleotide is operably linked to one or more heteroloqous control sequences that direct the production of the polypeptide in an expression host, wherein the polypeptide having xylanase activity is selected from the group consisting of:

• (a) a polypeptide having at least 95% sequence identity to the sequence of amino acids 19 to 414 of SEQ ID NO:
• 4;
• (b) a polypeptide encoded by a polynucleotide that hybridizes under high stringency conditions with (i) nucleotides 55 to 1242 of SEQ ID NO:
• 3 or (ii) a full-length complementary strand of (i), wherein high stringency conditions are defined as prehybridization and hybridization at 42° C. in 5×SSPE, 0.3% SDS, 200 μg/ml sheared and denatured salmon sperm DNA, and 50% formamide, followed by three washing steps each for 15 minutes using 2×SSC, 0.2% SDS at 65° C.;
• and
• (c) a polypeptide encoded by a polynucleotide having at least 95% sequence identity to the sequence of nucleotides 55 to 1242 of SEQ ID NO:
• 3.