Purification , Characterization , a d Production

We found two enzymes that solubilize pectin from protopectin, tentatively named protopectinase-N (PPase-N) and protopectinase-R (PPase-R), in a culture filtrate of Baeitltis subtitis IFO 3134. These enzymes were purified to homogeneity by hydrophobic, cation exchange and size exclusion chromatographies. The molecular weights of PPase-N and PPase-R were estimated to be 43,OOO and 35,OOO, respectiyely, by SDS-PAGE. Their pls were 9.4 and 8.2, respectiyely. These enzymes were stable in a wide range of pH and temperature. PPase-N and -R released water-soluble pectin by transeliminatiye c]eayage of protopectin, According to their substrate specificities and modes of action, PPase-N and PPase-R could be classified as endo-pectate transeliminase (pectate lyase; EC 4.2.2.2) and endo-pectin transeliminase (pectin Jyase; EC 4.2.2.10), respectiyely. Both enzymes were produced in a simple medium containing defatted soybean flour and phosphates. Production of PPase-N was repressed by addition of glucose while that of PPase-R was enhanced by phosphate.