A study of the sites of glycosylation of zein proteins using the lectin concanavalin A

The sites of glycosylation of zeins, the maize (Zea mays L.) storage proteins, were studied using the affinity of the lectin Concanavalin A (Con A) for certain glycosides. Zeins which were extracted from kernels of Illinois High Protein (IHP), W22, W64A and Oh43 were separated by isoelectric focusing and analyzed with a radiolabeled Con A binding technique. Certain sub-groups of the zein proteins contained carbohydrate moities which bound Con A while others did not. Zeins extracted from Oh43 kernels had a higher relative affinity for Con A than those of other maize lines. Further analyses of the zeins of Oh43 by gas chromatography demonstrated the presence of fucose, mannose and glucose.