About the Lectin

Phaseolus vulgaris includes a number of seed varieties, specifically the wax bean, pinto bean, tora bean, red kidney bean, and the black kidney bean. While much research has been done with the isolectins from the red kidney bean, little work has been done with the lectins found in the closely related seeds. Lectins isolated from these varieties may share some biochemical properties with the isolectins from the red kidney bean but are not identical. Some of the similar biochemical properties include: the ability to agglutinate both erythrocytes and leucocytes, the ability to induce a mitogenic response, and the general protein structure of the lectin. The black kidney bean was found to contain a non-specific blood agglutinin ¹ . Carbohydrate inhibition studies have been performed by EY Laboratories using a crude extract of the black kidney bean. In contrast to PHA-L and PHA-E, the black kidney bean lectin(s) is inhibited by simple sugars. More than 95% of the specific agglutinating activity is found in less than 30% of the material precipitated by ammonium sulfate. The only carbohydrate found to be completely inhibitory at a concentration of 0.1M was GalNAc. At the same concentration lactose is slightly inhibitory. Melibiose [Galα(1,6)Glc], N-acetyl-neuraminic acid, and galactose are also inhibitors, but they are less inhibitory than lactose. Glucose, GlcNAc, mannose, and fucose were all non-inhibitors, even at a final concentration of 0.1M. Please contact our technical services department for the availability of the purified lectin.

REFERENCES

1. Jaffe, W. G. and Hannig, K. (1965) Arch. Biochem. Biophys. 109: 80-91.