Talaromyces xylanases

A xylanase polypeptide comprises: (a) the amino acid sequence from amino acids 23 to 408 of SEQ ID NO:2; or a variant of (i) which is capable of cleaving xylan and has at least 70% identity to the amino acids 23 to 408 of SEQ ID NO:2. The polypeptide is obtainable from a fungus or an organism of the genus Talaromyces such as the species Talaromyces emersonii. Polynucleotides, vectors, host cells and composition are described. A plant or xylan-containing material can be treated, to degrade, hydrolyse, modify xylan in the material, degrade or modify plant cell walls or cleave xylopyranosyl or b-D-xylan subunits of the material, by contacting the material with the protein. The polypeptide can also be used in a method of treating plant material, improving filterability and/or reducing viscosity of xylan-containing liquids, improving filterability or clarifying alcoholic liquids (e. g. beer, wine) or fruit or vegetable juices, hydrolysing agricultural residues, in recycling materials (e. g. containing paper) in paper making for thickening foodstuffs and/or extracting desirable materials (e. g. coffee, plant oil, starch), processing plant pulp, juice or extract, improving loaf volume, bread quality or reducing the stickiness of dough, in brewing, beer or wine-making, distilling, recycling, biomethanation, dental hygiene, leather treatment, paper manufacture, fruit or vegetable juice or extract treatment, textile treatment or manufacture, baking or bread making, treating flower bulbs, preparation of food or foodstuffs or in an animal feed.