Enzyme mechanisms involved in cellulose hydrolysis by the rot fungus <i>Sporotrichum pulverulentum</i>

Abstract

Abstract This article presents a review of the enzyme mechanisms involved in degradation of cellulose by the white‐rot fungus Sporotrichum poulverulentum . The hydrolytic enzymes involved include: (1) five endo‐1,4‐β‐glucanases; (2) one exo‐1,4‐β‐glucanase, and (3) one or several 1,4‐β‐glucosidases. A recently discovered oxidative enzyme of importance in in vitro cellulose degradation seems to be a cellobiose oxidase. An oxidoreductase, cellobiose:quinone oxidoreductase, is of importance both in cellulose and in lignin degradation. Regulatory mechanisms of the extracellular enzyme activities, such as monosugar levels causing catabolite repression of the endoglucanases, have also been investigated. The enzymes used by S. pulverulentum in cellulose hydrolysis are compared to those used by Trichoderma viride . Very similar types of enzymes are used in both cases. However, no oxidative enzyme has so far been found to be involved in extracellular cellulose degradation in the case of T. viride . Recommendations for further research are given.