PURIFICATION, PROPERTIES AND FACTORS AFFECTING THE ACTIVITY OF TRICHODERMA-VIRIDE CELLULASE

Cellulases produced by Trichoderma viride grown on wheat bran were fra ctionated by ammonium sulphate (50%) and purified by chromatography on DEAE-Sephadex A50 followed by CM-Sephadex C50. The overall purificati on method showed a protein reduction of 99.8% of the original protein content of the culture filtrate. On the other hand the specific activi ty was increased about 228-fold. Amino acid analysis of the purified e nzyme showed that glycine was the predominant one followed by glutamic acid, serine, alanine and leucine. Cysteine and tyrosine were the lea st common amino acids. Electrophoresis by Disc-PAGE showed that the pu rified enzyme was homogeneous since it gave only one distinctive band. The enzyme had a MW of 58 000 as indicated by SDS-PAGE. The isoelectr ic point of the enzyme was 5.7. The cellulolytic activity was directly proportional to the enzyme concentration and was substrate-dependent. The maximum enzyme activity was found at pH 5 when incubated at 45-de grees-C for 30 min.