Provided are isolated polypeptides having xylanase activity, catalytic domains and cellulose binding domains, and polynucleotides encoding the polypeptides, catalytic domains or cellulose binding domains. Also provided are nucleic acid constructs, vectors and host cells comprising the polynucleotides as well as methods of producing and using the polypeptides, catalytic domains or cellulose binding domains.
STATEMENT AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT
 This invention was made with Government support under Cooperative Agreement DE-FC36-08GO18080 awarded by the Department of Energy. The government has certain rights in this invention.