EXTRACELLULAR CELLULOLYTIC COMPLEX FROM MORCHELLA-CONICA - PRODUCTION AND PURIFICATION

A cellulolytic complex was obtained from the ascomycetes Morchella conica grown on a mineral medium with a cellulose powder as the substrate. Maximum yield of the activities tested (carboxymethylcellulase, avicelase, filter paper, cotton activity, cotton degrading activity and β-glucosidase) was reached at 8 d of fermentation. Optimum activity conditions were found at pH 5 and 60°C for CMCase; 4.5 and 40°C for AVase. Half-life at 45 and 50°C was longer than 96 h for both CMCase and AVase. The crude enzyme, after ultrafiltration and dialysis, was purified by DEAE-Sepharose CL 6B ion-exchange chromatography. The 'cellulase' was separated into four fractions which were characterized with both polyacrylamide-gel- and SDS- electrophoresis. Three different endoglucanases (Endo I, Endo II and Endo III and three different cellobiohydrolases (Exo I, Exo II and Exo III) were assessed, the Exo I was present in the form of three isoenzymes.