TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preparation (Claimed): The polypeptide is prepared by culturing the cell under suitable conditions and recovering the polypeptide. Preferred Polynucleotide: The polynucleotide is a DNA sequence. The nucleic acid construct has gc content of 58-65%, preferably 56% or more, more preferably 58% or more. Preferred Polypeptide: The polypeptide has acetyl xylan esterase activity. Preferred Cell: The cell is a eukaryotic cell, preferably fungal cell. The fungal cell is comprises Aspergillus, Trichoderma/Hypocrea, Fusarium, Disporotrichum, Penicillium, Acremonium, Neurospora, Thermoascus, Myceliophthora, Sporotrichum, Thielavia, Chrysosporium, humicola, Neurospora and Talaromyces. The cell is deleted, knocked-out or disrupted in full or portion of one or more genes, where optionally the gene encodes for a protease. Preferred Components: The cellulase is cellobiohydrolase, cellobiohydrolase I, cellobiohydrolase II , endo- beta -1,4-glucanase, beta -glucosidase or beta -(1,3)(1,4)-glucanase. The hemicellulase is endoxylanase, beta -xylosidase, alpha -L-arabinofuranosidase, alpha -D-glucuronidase, acetyl xylan esterase, feruloyl esterase, coumaroyl esterase, alpha -galactosidase, beta -galactosidase, beta -mannanase or beta -mannosidase. The pectinase is endo polygalacturonase, pectin methyl esterase, endo-galactanase, beta -galactosidase, pectin acetyl esterase, endo-pectin lyase, pectate lyase, alpha -rhamnosidase, exo-galacturonase, expolygalacturonate lyase, rhamnogalacturonan hydrolase, rhamnogalacturonan lyase, rhamnogalacturonan acetyl esterase, rhamnogalacturonan galacturonohydrolase, xylogalacturonase, alpha -arabinofuranosidase or endo-arabinanase. Preferred Composition: The composition comprises ligninase, expansin, expansin-like polypeptide, swollenin or the polypeptide product of a gene encoding a cellulose integrating protein or a cellulose induced protein. Preferred Method: The treatment involves degradation and/or modification of cellulose and/or hemicellulose and/or a pectic substance. EXAMPLE - No suitable example given.