引言在可持续发展、低碳经济的背景下,利用纤维素酶水解木质纤维原料生产燃料乙醇无疑是一项符合我国国情的能源战略‘“。然而纤维素酶的水解效率低是制约纤维素燃料乙醇生产的最大障碍。
This research was to prove whether there is some special protein in cellulase-producing microorganism acting as a cellulase-activity-enhaneing protein, thus exploring its potential application in lignocellulose hydrolysis. An extracellular protein without eellulase activity was separated and purified from culture medium of Trichoderma Koningii through a series of procedures, including ultrafiltration, ammonium sulfate precipitation, oetyl-Sepharose CL-4B and Sephadex G-75 column chromatography. The molecular weight of the prtotein was estimated to be 30 × 103 by SDS-PAGE. With the addition of this protein (400/ug per g filter paper) into the reaction mixture containing filter paper and cellulase (0.06 IU per g filter paper ), the reducing sugar released during 48 h was observed to increase greatly, 104.9% greater than that of the control hydrolysis. Moreover, it was found that this purified protein enhanced the activity of exoglueanase, one of the three components of fungi cellulase, while endoglucanase and β- glucosidase activities did not change much. Mass spectrometry analysis indicated that this purified protein was an unknown protein. Based on these results, this purified extracellular protein originated from Trichoderma Koningii could be regarded as a cellulase activity-enhancing protein, which was different from the reported plant expansin and swollenin.