PURIFICATION AND CHARACTERIZATION OF STRICTOSIDINE BETA-D-GLUCOSIDASEFROM CATHARANTHUS-ROSEUS CELL-SUSPENSION CULTURES

Strictosidine beta-D-glucosidase (EC 3.2.1.105) was purified to appare nt homogeneity from suspension cultured cells of Catharanthus roseus ( L.) G. Don (Apocynaceae). It occurs in cell extracts as a high molecul ar mass protein complex. Native PAGE analysis showed the occurrence of three different forms. Digestion of the protein by trypsin resulted i n disintegration of the complex, solubilising the enzyme without loss of activity. In cell extracts, the native enzyme forms probably consis t of several subunits of 63 kDa. Determination of kinetic parameters s howed that it has a strong affinity for the substrate (strictosi dine, K(m )less than or equal to 20 mu M). (C) Elsevier, Paris.