Regulatory Controls in Relation to Overproduction of Fungal Cellulases
A growing trend in the development of viable processes for the conversion of renewable cellulosic biomass to glucose is the use of microbial cellulases as biological catalysts. Unfortunately, the cost of the cellulase enzymes has been prohibitive for large scale industrial application in saccharification of cellulose. The high cost of cellulase is due largely to the low yield and to the low specific activity of enzymes from the available microbial strains. Improvement of the cellulolytic microbial strains can be considerably enhanced through selective screening programs. However, the rationale for selection and the chance of isolation of more useful strains are hampered by our lack of understanding of mechanisms controlling the synthesis and secretion of cellulase. Successful genetic cloning and expression of the cellulase genes from Tviohodevma or any other cellulolytic microorganism is similarly dependent upon a sound basic knowledge of the control mechanisms. Tviohodevma genetics is an unexplored abyss. Although Tviohodevma is reported to have a sexual stage, in the Hypoovea (1,2) mating types are generally unavailable. Thus, traditional methods of delineating genetic linkages are elusive.
KeywordsRegulatory Control Extracellular Protein Cellulase Production Catabolite Repression Cellulase Enzyme
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