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Cellulose is the Earth rich renewable resources, to microbial its degradation, into raw materials for human use, the cellulase is low-carbon, green biological protein applied to the pharmaceutical and other fields. Nearly half a century, the scholars of cellulase extensive research in the cellulase protein metabolic regulation mechanism, the interaction between the enzyme protein, how to improve the activity of the enzyme protein applications achieved encouraging research. But these are mostly based on Trichoderma (Trichoderma), represented by the fungi as an object of study, few studies of bacterial cellulase production. In this paper, the source of bovine rumen fluid as a screening cellulose-degrading microbes bacteria screening to a higher production of cellulase activity of bacteria. The main findings are as follows: screened 11 wild mushroom with the degradation of cellulose activity from bovine rumen fluid. Improvement on traditional screening medium, having a composition of 0.5% CMC, 0.2% NaNO3, 0.1% K2HPO4, 0.05% KC1, 0.05% MgSO4-7H2O, 0.0001% FeSO4, 1.6% agar. Hydrolytic ring size can be changed by adjusting the content of the medium in the CMC, the filter medium to reduce the photocopying process. 2. Of strain N07 screened from morphological, physiological and biochemical experiments and 16S rDNA sequence analysis identified the organism as a fiber Aeromonas named Cellulomonas uda NJ0807 Cellulomonas uda NJ0807 culture fermentation of cellulose enzyme conditions were optimized. BBD (Box-Behnken Design) on the basis of the single factor test, response surface experiment optimize cellulase production fermentation conditions, the strain in the composition to 1% peptone, 0.5% sucrose, 1% CMC, 0.3% NaCl, 0.1% K2HPO4, 0.04% MgSO4-7H2O, initial pH 7.7, inoculum size of 5%, 23 ° C, 180 r · min-1 fermentation 53 h, the enzyme activity reached 1.35U · mL-1.4. using fast protein liquid chromatography (FPLC) anion exchange and gel filtration chromatography combined method of Cellulomonas uda NJ0807 metabolites cellulase separation and purification, to give three major endoglucanase component; were identified by electrophoresis on SDS-PAGE, and the relative molecular mass of 66 kDa, 40 KDa and 31 KDa, the purified cellulase activity was 11.76U · mg-1 of 36.4U · mg-1 and 72.4 U-MG-1 5 purified 40 kDa fiber the prime enzyme hydrolysis of CMC optimum reaction temperature of 50 ° C, the optimum reaction pH 6.0, the Km value of 11.4 mg-mL-1 Vmax 224.2μmol · L-1 · min-1. Good thermal stability of the cellulase in the 40 ° C to 50 ° C when still in the range of pH5 ~ 9 the cellulase is relatively stable.
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