A SIMPLE AND NONDESTRUCTIVE METHOD FOR THE SEPARATION OF POLYSACCHARIDES FROM BETA-GLUCOSIDASE PRODUCED EXTRACELLULARLY BY ASPERGILLUS-NIGER

An apparatus based on electrophoresis has been devised that removes no ncovalently bound polysaccharides from extracellular proteins of Asper gillus niger with concomitant partial beta-glucosidase purification an d concentration. The apparatus consists of a series of three chambers separated by polyacrylamide gels. Dialyzed and concentrated crude extr act of Aspergillus niger containing beta-glucosidase was poured into t he middle chamber, while smaller anodic and cathodic chambers containe d buffer. When electric current was applied negatively charged protein -polysaccharide complexes moved toward the anode. Most of the negative ly charged proteins, including beta-glucosidase, crossed the gel barri er into the anodic compartment, while neutral polysaccharides were eit her trapped in tile gels or remained in the middle chamber. In this wa y, 125 ml of dialyzed and concentrated crude extract of Aspergillus ni ger was processed. Therefore, after 24 h of electrophoresis, 68% of th e proteins and 90% of the beta-glucosidase activity, but only negligib le amounts of polysaccharide, were transferred to the anodic chamber T he removal of high-molecular-weight polysaccharide from beta-glucosida se had a detrimental effect on the stability of the enzyme.