B - glucosidade mutant, DNA, vector, expression, cell transformed, composition of enzyme for decomposing biomass and method for producing a solution of sugar from biomass derived from cellulose

摘要

Provided is a novel ²-glucosidase exhibiting high activity in the presence of biomass and having high thermal stability compared to conventional enzymes. The ²-glucosidase includes substitutions and/or deletions of amino acids, i.e., at least three amino acids selected from the group consisting of Glu39, Asp169, Arg170, Arg220, Tyr227, and Glu330, of the parent ²-glucosidase with other amino acids and shows a cellobiose decomposition activity.