Filamentous Fungi Fusarium Of Fusarium Oxysporum, L19 Thermophilic Endoglucanase,

Cellulose is a most abundant biomass resource in the world, existing as a main plant cell wall component. The importance of its effective utilization through its conversion to fuels and chemicals is widely recognized when considering the crucial effect of cellulose degradation in carbon cycling and the potential exploitation of cellulose as a main way to settle the problem of resource scanty. Although the action of cellulases has been extensively studied in biochemical terms, there are still multipronged constraints to utilize the cellulose as a low-cost and environment-friendly energy resource. This is probably because of the high cost of cellulase proceeded from the low hydrolysis rate of most cellulases and the apparently loss of enzyme activities during the catalytic reaction, which is the bottleneck in the industrial utilization of cellulose.A great deal of efforts has gone into the development of extreme enzymes, such as thermophilc cellulases, alkalitolerant cellulases and acidictolerant cellulases to enhance enzyme stability. But few of these extreme enzymes was applied into the industry because of their natural low catalytic efficiency. To consider the enzymatic hydrolysis reaction from the catalytic kinetics, the main effect factors to the enzymatic catalytic rate should cover the catalytic environment that is the conditions in addition to the interaction of enzyme with its substrate, during which the temperature and pH value on the speed of enzyme reaction and stability of enzyme is of particular importance. In fact, it is inconsistent in thermoactivity and thermostability of the enzyme at the accustomed temperature optima as a result of the method to determine the optimal temperature. At the "optimal temperature", enzyme would be unstable and inactive which is bound to shorten the useful life of enzyme and increase the cellulose conversion cost. Owing to the different stability of enzyme protein at various pHs, the "pH-Velocity" curves would appear non-normal distribution which restrict the reliability of expression the hydrogen ion concentration by pH and bring many mistakes.