Carbohydrate binding specificity of the lectin from the pea (Pisum sativum).

Hapten inhibition measurements on the precipitin reaction between Pisum sativum lectin and Pichia pinus phosphomannan showed the lectin to bind D-mannose, D-glucose, D-fructose and L-sorbose. Unmodified hydroxyl groups at the C-4 and the C-6 positions of the D-glucopyranose ring were essential for binding to the protein. Modification of the C-2 hydroxyl group was allowed in the D-glucopyranose ring but not in the D-mannopyranose configuration. Substitution of the hydroxyl hydrogen atom at the C-3 position of D-glucose increased the binding efficiency. With the exception of gentiobiose, the beta-linked glycobioses tested were not bound to the lectin, whereas the alpha-linked glycobioses were potent inhibitorsmin general, the P. sativum lectin was found to be less sensitive to structural variation of inhibiting carbohydrates than concanavalin A, the lectin from Canavalia ensiformis.