Studies on lectins. LVIII. Sugar-binding properties, as determined by affinity electrophoresis, of alpha-D-galactosidases from Vicia faba seeds possessing erythroagglutinating activity

The interaction of alpha-D-galactosidases from Vicia faba seeds with saccharides was studied by means of affinity electrophoresis on polyacrylamide gel in an acidic buffer system. For the preparation of affinity gels, water-soluble O-glycosyl polyacrylamide copolymers and polysaccharides were used. alpha-D-Galactosidases interact with immobilized O-alpha-D-galactosyl residues and glycogen, but no interaction was observed with immobilized O-alpha-D-mannosyl residues. On the basis of the results of affinity electrophoresis performed in the presence of various free sugars, dissociation constants of the various alpha-D-galactosidase-free sugar complexes were calculated.