Mechanism of Cellulase Action on Cellulose Structure

Abstract

The mode of degradation of native cellulose has not been fully established. The mode of hydrolysis of highly purified cellulases, exo- and endo-type cellulases from fungi (Irpex lacteus, Trichoderma reesei and Aspergillus niger) were investigated by using pure cellulosic materials with different crystallinities of cellulose I type in addition to bacterial celluloses of two type different types (cellulose I and II) and valonia cellulose. At the same time, we also investigated the hydrolysis action of exo- and endo-type cellulases by using water soluble substrates such as cellooligosaccharide and barley glucan. From these results, it was found that the characteristic mode of action of each cellulase can be clearly understood by using only pure crystalline cellulosic substrates. Furthermore, we will describe the synergistic actions of cellulase components in addition to related enzyme on cellulose degradation in this paper.