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To improve the efficiency of enzymatic saccharification for lignocellulose, an efficient crude multi-enzyme was produced by Trichoderma reesei using corncob, a low cost inducer. Expression of cbh1, bgl1, egl1, xyn1 and positive regulator xyr1 induced by corncob increased significantly compared to that by cellulose. After 120 h induction by corncob, enzymatic activities on filter, CMC, β-glucose and xylan increased 86.5, 46.9, 120.9 and 291.2% compared to those induced by cellulose, and the concentration of secreted protein increased by 120.8%. FPase:β-glucosidase and FPase:xylanase values in crude multi-enzyme I (ECI, induced by corncob) were higher than that in crude multi-enzyme II (ECII, induced by cellulose). Under the same hydrolysis conditions, the volume dosage of ECI was only half of ECII, but ECI still showed a maximum of 12.5 and 33.4% higher than ECII in the total reducing sugar and glucose yield in lignocellulose hydrolysis. Corncob could be a candidate for low cost production of multi-enzyme for efficient lignocellulose degradation, and this work could guide the genetic modification of T. reesei to obtain efficient multi-enzyme for lignocellulose hydrolysis. [ABSTRACT FROM AUTHOR]

• Four fusion enzymes of SWOI and XYNⅡ from T. reesei were constructed. • The connection order and linker have significant influence on the fusion enzymes. • SWOI-XYNⅡ and SWOI-(GGGGS) 2 -XYNⅡenhance the activity and binding of xylanase onto corn cobs. • Synergism of SWOI-XYNⅡ and SWOI-(GGGGS) 2 -XYNⅡwith EGⅡ greatly boosted lignocellulose hydrolysis. Low enzymatic hydrolysis efficiency prevents the economic biotechnological conversion of lignocellulose to valuable products. To improve the lignocellulose degradation, artificial fusion enzymes of swollenin (SWOI) and xylanase (XYNⅡ) from Trichoderma reesei were constructed and utilized in lignocellulose hydrolysis. Different connection modes between swo1 and xyn2 were shown to have a significant effect on the activity of the fusion enzyme. Xylanase activity of fusion enzyme SWOI-XYNⅡ (S-X) obtained by connecting C-terminal of SWOI and N-terminal of XYNII increased, while that of XYNⅡ-SWOI (X-S) decreased. Xylanase activity of SWOI-(GGGGS) 2 -XYNⅡ (S-2X) with a connecting peptide (GlyGlyGlyGlySer) 2 between SWOI and XYNII was further improved comparing to that of S-X. Compared with XYNII, S-2X improved the production of reducing sugar from alkali-treated corn (Zea mays L.) cob by 42 %. When acting on alkali-treated corn cob together with endoglucanase EGII, S-2X increased the yield of reducing sugar by 58 % comparing with XYNII. The swollenin-xylanase fusion enzyme was proved to be conducive to plant cell wall decomposition and could be a promising candidate to enhance the efficiency of enzyme cocktails for lignocellulose degradation. [ABSTRACT FROM AUTHOR]