Glycosidase Semi-quantitative Gel Electrophoresis Of Aspergillus Functional Proteomics Preliminary Applications

With the development of the word economy, global resource crisis is being more and more serious. It is supposed that available petroleum will run out in the coming decades, and resource crisis has already been a general and urgent problem. Cellulose, the most abundant component of plant biomass, is not fully utilized. Therefore, efficient bioconversion of cellulose has attracted universal attention in recent years.Because of the heterogeneity of substrate and the diversity and complexity of cellulase system's synergy,the progress of the research of cellulosic biomass conversion is slow,and the technology of conversion straw biomass into fuel ethanol has yet to enter the large-scale industrial production.Depth study the relationship of substrate's nature and the enzyme component of structure-activity can lay a theoretical foundation.Aspergillus niger has a clear genetic background,and a very high protein secretion capacity. Studying its extracellular cellulase enzymes system will develop new strategies of biodegradable of cellulose,and has its great practical significance of biodegradable of cellulose. In this paper, we begin the research with the chemical composition of straw-type substrate and its ultrastructure analysis,and set A. niger as center,we studied the dynamic changes of its extracellular enzymes components and the correlation between its extracellular functional components and the degree of polymerization as well as chemical composition. We achieved the following results:Through the frozen section and the semi-thin section technique, combined with the characteristics-stain technique,it is showed that the distribution of chemical composition of corn stover lignocellulose substrate isdifferent,and its supramolecular structure is heterogeneity and delamination.The hydrolyzation by enzymes shows the tissue-specific laws of degradation.Through protein-electrophoresis and Native-PAGE,combined with digital image processing technology,we establish the semi-quantitative electrophoresis of glycoside hydrolase.By this method,we can measure the enzyme such as cellulase, xylanase and glucosidase,as well as proteins which can absorpt on carbohydrate.We use this method dothe study on Aspergillus niger AN76,we find that there is at least one glucosidase,3 xylanase and 4 cellulase enzyme.We also do the research of PMF on 15 kinds of AN76 extracellular protein.Culturing of Aspergillus niger AN76 through different carbon sources,and using semi-quantitative electrophoresis, we find that glucosidase is constitutive enzyme, xylanase and endoglucanases are induced enzyme;monosaccharide(glucose, xylose) can induce the expression of xylanase I, II, xylan can induce the expression of xylanase III and endoglucanase II;while CMC can induce other components except endoglucanase IV, glucanase IVcan express on corn straw. We assumed that the different degree of polymerization of oligosaccharides are involved in regulating the expression of enzyme molecules.