Purification and characterization of pectinesterase and polygalacturonase from Trichoderma reesei

Abstract Exopolygalacturonase, endopolygalacturonase and pectinesterase were separated from culture filtrates of Trichoderma reesei QM9414 by Sephadex chromatography. Exopolygalacturonase was characterized by specific cleavage of pectic acid to form d -galactopyranuronic acid, and by the hydrolysis of oligomers (highest reaction rate at pentamer). Polygalacturonase exhibited 2 pH-optima peaks (at 4.8 and 5.1) and 10 bands with enzyme activity by isoelectric focusing (IEF) (p I 4.6–8.5). Pectinesterase showed a pH-optimum at 7.6, and 6 enzyme-activity bands on an IEF zymogram which seemed identical with those of higher plants (tomato, alfalfa).