Immunoelectrophoretic studies with bean proteins

Abstract The immunoelectropherograms of twenty-four extracts from different varieties of kidney beans ( Phaseolus vulgaris ) differed from each other, revealing between eight and eleven precipitation lines. A crystalline protein and a pure globulin from black beans gave identical immunological reactions although they were different in chemical composition. The antisera from rabbits sensitized with this crystalline protein produced one or two precipitation lines with the extracts of different beans. Nineteen of the bean extracts had haemagglutinating activity. The corresponding extracts originated one or two precipitation lines which could be stained with sudan black, indicating the presence of lipoproteins; none of the haemagglutinin-free extracts originated stainable immunoprecipitates. It is concluded that the bean phytohaemagglutinins are probably lipoproteins.