Xylanases, nucleic acids encoding them and methods for making and using them

摘要

The invention relates to enzymes having xylanase, mannanase and/or glucanase activity, e.g., catalyzing hydrolysis of internal β-1,4-xylosidic linkages or endo-β-1,4-ghicanase linkages; and/or degrading a linear polysaccharide beta-1,4-xylan into xylose. Thus, the invention provides methods and processes for breaking down hemicellulose, which is a major component of the cell wall of plants, including methods and processes for hydrolyzing hemicelluloses in any plant or wood or wood product, wood waste, paper pulp, paper product or paper waste or byproduct. In addition, methods of designing new xylanases, mannanases and/or glucanases and methods of use thereof are also provided. The xylanases, mannanases and/or glucanases have increased activity and stability at increased pH and temperature.

主权项

1. An isolated, synthetic or recombinant nucleic acid comprising:
(a) a nucleic acid of SEQ ID NO: 383; wherein the nucleic acid encodes a polypeptide having a xylanase activity (b) the nucleic acid of (a), further comprising modification of the nucleotides at residues 40 to 42, wherein the nucleotides are modified to CAC or CAT and wherein in the nucleic acid encodes a polypeptide having a xylanase activity, or (c) a nucleic acid encoding a polypeptide having a xylanase activity, wherein the polypeptide comprises thea sequence of SEQ ID NO: 384.