The mechanism of enzymatic cellulose degradation (II). Mode of action of cellulose hydrolyzing enzyme from Aspergillus niger UC.

Abstract

Purified Avicelase and CMCase from a mutant Aspergillus niger UC hydrolyzed cellotetraose, and cellohexaose releasing glucose, cellobiose and cellotriose. The enzymes showed a straight line slope (1/η sp. /reducing sugar) with a roughly 45° angle in the relationship between the decrease in viscosity and the increase in the reducing sugar from CM-cellulose. The enzymes also hydrolyzed 4-methylumbelliferyl (MU) trisaccharide and 4-MU disaccharide at a different rate. We obtained no evidence that this cellulase is an exo-type one so far named cellobiohydrolase (CBH) as the systematic nomenclature.