Enzymology of cellulose degradation

In the last few years there has been a considerable improvement in the understanding of the mechanisms involved in the microbial degradation of cellulose, but there are still many uncertainties. As presently understood, it would appear that different mechanisms may operate in the various types of microorganism. Thus degradation of crystalline cellulose is effected by anaerobic bacteria by large Ca-dependent and thiol-dependent multicomponent endoglucanase-containing complexes (cellulosomes) located on concerted action of endo-and exo-glucanases which act some distance from the cell which renders cellulose soluble. All of the endo-and exo-glucanases possess a bifunctional domain structure: one contains the catalytic site, the other is involved in binding the enzyme to crystalline cellulose.