| Abstract: | The tuberous roots of winged bean (Psophocarpus tetragonolobus (L.) DC) contain two distinct groups of lectins corresponding to the acidic and basic lectins of the seed. The tuber isolectins were separated by chromatography on Ultrogel AcA44 and SP-Sephadex C-25, and purified by affinity chromatography. The acidic and basic lectins were also isolated from tuber extracts in a single step by affinity chromatography on lactose-Sepharose 6B and melibiose Bio-Gel P150, respectively. The lectins isolated from the tubers of six varieties of P. tetragonolobus showed no significant differences in their properties. The molecular and physicochemical properties of the tuber acidic and basic lectins were essentially identical to that of the corresponding winged bean seed lectins; the only exception was a small difference in the isoelectric points of the subunits of acidic lectins of seed and tuber as observed on isoelectric focusing in 8 m urea. |
