Characterization of Con C, a lectin from Canavalia cathartica Thouars seeds

Con C, a lectin from Canavalia cathartica, a wild species of Canavalia was isolated and partially characterized. Mannose–agarose resin was used as an affinity matrix for purification. The lectin showed strong agglutination activity (2.34 AU/ng protein) towards rabbit erythrocytes. Con C agglutinated A, B and O groups of human blood with a preference for A and O groups. The native molecular weight of lectin was 62 kDa and the subunit molecular weight was 31 kDa. No carbohydrate moiety was found to be associated with the lectin. Con C showed a broad pH optima of pH 4–8. Total inactivation of lectin activity occurred at 70 °C when heated for 10 min. The lectin was found to be mitogenic for mouse-spleen cells (total). N-terminal analysis revealed 94% homology with C. ensiformis lectin (Con A). C. cathartica is a legume with high nutritional values and less antinutritional factors and the potential of the same is yet to be exploited.