Method of improving the activity of cellulase enzyme mixtures in the saccharification (ligno)cellulosic material

A composition for the degradation and saccharification of (ligno)cellulosic materials comprising a mixture of enzymes obtained from a modified fungus,

• wherein said composition has one or more enzymes having cellulase or hemicellulase activities, and lacks or has reduced levels or activities of one or more enzymes responsible for the production of one or more products selected from the group consisting of cellobionolactone, cellobionic acid, gluconolactone, and gluconic acid;
• wherein production of glucose with said composition in the presence of (ligno)cellulosic materials is enhanced above the endogenous level of glucose produced with a composition which has normal levels or activities of one or more enzymes responsible for the production of one or more products selected from cellobionolactone, cellobionic acid, gluconolactone, and gluconic acid.

A method of increasing saccharification of cellulosic materials comprising:

• treating the cellulosic material with an enzyme composition comprising enzymes having one or more cellulase or hemicellulase activities;
• wherein the enzyme composition is obtained from a modified fungus comprising one or more modified genes encoding enzymes responsible for the production of one or more products selected from cellobionolactone, cellobionic acid, gluconolactone, and gluconic acid;
• wherein the level of expression of said modified genes is eliminated or reduced or the level of activity of modified enzymes encoded by modified genes is reduced or eliminated, compared to the endogenous level of expression or activity in a parent fungus lacking one or more of said modified genes.