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Cellulase is mainly divided into three categories: (1) dextran exonuclease (exo-1 ,4-β-D-glucana-ses), also known as cellobiase (cellobiohydrolases, CBH); (2) endoglucanase (Endo-1, 4 - beta-D-glucanases, referred to as EG); (3) β-glucosidase (1,4-β-D-glucosidases referred to as BG), three the synergistic effect of the components, and ultimately will be the hydrolysis of cellulose to produce glucose; the cellulase production bacteria wire fungi, especially Trichoderma, Aspergillus, Trichoderma cellulase production is mainly endoglucanase and Portugal glycans exonucleases, while Aspergillus primarily the ability of producing β-glucosidase. Synthesis of cellulase by the cellulose, lactose (LACTOSE), cellobiose (cellobiose), Cassia the disaccharidic (sophorose), and L-sorbose (L-Sorbose) induction. This paper, L-sorbose induced of Trichoderma viride AS3.3711 cellulase gene transcription induced 9-12h, the endoglucanase of the amount of mRNA transcripts peak collected mycelium extract total RNA and Reverse recorded cDNA. The single-stranded cDNA as a template, PCR amplification of a cDNA gene encoding endoglucanase enzyme I (egl1) and endonuclease III cDNA gene encoding endoglucanase (egl3), removal of the signal peptide of egl1, and egl3 sequence were constructed the the recombinant plasmid the pET-egl1 and pSE-egl3, and its expression in Escherichia coli. SDS-PAGE analysis of the expression product of E. coli, the results showed that the the egl1 gene expressed in E. coli and a protein molecular weight of approximately 46.2kDa; the egl3 gene expression in E. coli a protein molecular weight of about 42kDa. CMC enzyme activity detected in the E. coli expression EGI no enzymatic activity, expressed in E. coli EG Ⅲ detected intracellular enzyme activity per ml of broth contained in endoglucanase activity was 0.04U/ml. Egl1 gene containing a signal peptide, was cloned into the yeast expression vector pYES2, constructed recombinant plasmid pYES2 was-egl1 transforming Saccharomyces cerevisiae INVscl the expression of β-D-galactose induced EGI, with Congo Red staining screening recombinant transforming sub. Saccharomyces cerevisiae is able to identify the EGI itself carry a signal peptide, while the expression product is secreted into the extracellular to the Congo Red staining detected in the filter plate, and therefore in the CMC, clear hydrolysis lap. With 80% saturation of ammonium sulfate precipitated protein enzyme from 2ml broth supernatant, and resuspended in 1 ml of a 0.05M sodium citrate buffer (pH 4.8), CMCase assay showed the Saccharomyces cerevisiae INVsvl expression of EGI optimum The reaction temperature was 47 ° C and optimum pH of 5.2, induced 70h activity reached a maximum value, approximately 0.08U/ml.
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