PURIFICATION AND CHARACTERIZATION OF CELLULASE FROM LEAF ABSCISSION ZONES OF COLEUS

Cellulase (1, 4 (1,3; 1,4) beta-D-glucan 4-glucanohydrolase, EC 3.2.1. 4), as determined by capacity of hydrolysis of carboxylmethylcellulose (CMC), has been purified from leaf abscission zones of coleus (Coleus blumei Benth cv. Ball 2719 Red) by a combination of gel filtration, a nd anion exchange and affinity chromatography. Both silver-stained SDS -PAGE and cellulase activity-stained native PAGE exhibited 2 bands in purified protein, suggesting two isoenzymes. The 2 protein bands with molecular masses of 56 and 62 kDa were apparently monomers. A test of cellulase activity indicated high levels of activity at pH 5 and pH 7. 2. Cellulase activity increased with an increase in reaction temperatu re to 50 degrees C. Purified cellulase showed no activity towards inso luble cellulose as determined by production of glucose and cellobiose.