Regulation of the formation and conversion of intermediate cellooligosaccharides and cellobiose during ezymatic hydrolysis of insoluble cellulose
Klésov, A.A.
Biokhimiia 47(4): 608-618
1982
ISSN/ISBN: 0320-9725 PMID: 7200805 Document Number: 189565
A kinetic analysis of the main regularities for formation and consumption of the intermediate metabolites (i.e. cellooligosaccharides and cellobiose) in the course of enzymatic hydrolysis of cellulose has been performed. The boundary relationships between the velocities of the individual steps of hydrolysis controlling the transition of the multienzyme cellulase system to be steady-state with respect to the intermediate metabolites were revealed. Using the kinetic approaches developed here, the values of the steady-state concentrations of insoluble intermediate oligosaccharides were determined experimentally for a number of cellulases from the fungi Trichoderma and Geotrichum. It was shown experimentally that when studying the kinetics of enzymatic hydrolysis of cellulose it is necessary to take into account the structural irregularities of the insoluble substrate even when a practically negligible fraction of it (with respect to its weight) is converted to soluble products. In other cases the kinetic parameters obtained could not be corresponding to the actual reactivity of the cellulose/cellulase system, reflecting rather a difference in reactivity between the labile (amorphous) and stable (crystalline) fractions of a cellulose substrate.