Method to improve the stability and broaden the pH range of family G/11 xylanases

摘要

The present invention relates to protein engineering, and concerns especially family G/11 xylanases, and genes encoding said enzymes. In specific, the invention concerns Trichoderma reesei XYNII gene, which codes for endo-1,4-β-xylanase (EC 3.2.1.8). The invention describes how site-directed mutagenesis can be used to improve the properties of an enzyme to match the industrial conditions where it is used. Protein engineering can be used to improve thermoactivity and thermostability of xylanases, as well as to broaden their pH range.

主权项

1. A recombinant gene encoding a variant xylanase having increased thermo stability or pH-stability when compared to a corresponding wild-type enzyme, wherein said variant comprises at least 95% sequence identity over the full length amino acid sequence of SEQ ID NO: 13, said variant having amino acid substitutions at positions corresponding to amino acids 2 and 28 of SEQ ID NO: 13.