Lectin variability in Phaseolus coccineus

Lectin variability within Phaseolus coccineus is revealed by non-denatured electrophoretic patterns and immunological labelling of total seed protein extracts, showing that the different cultivars and wild varieties studied can be classified into three main categories according to the number of isolectins (three, two or one) present in each extract. Attempts in the purification of these isolectins were performed on three different affinity systems in which ligands were thyroglobulin (known to purify the P. vulgaris isolectins), pig red cell membrane ghosts (stroma) or antibodies against the P. vulgaris cv. Contender E₂L₂ isolectin. The P. coccineus isolectins exhibit varied affinities towards thyroglobulin and stroma, the cathodic and anodic (pH 4.5) isolectins being respectively retained by the two systems, whereas the antibody affinity system is the only one able to purify the totality of the isolectins present in an extract.