An -N-acetyl-D-glycosamine binding lectin from Bandeiraea simplicifolia seeds.

An cY-n-galactopyranosyl binding lectin (1) was recently isolated and characterized from the seed extracts ofBandeiraea simplicifolia. While pursuing further studies on this lectin, a second protein capable of interacting with p-azophenyl 2-acetamido-2deoxy-aand -p-n-glucopyranoside BSA’ conjugates was discovered. The new lectin, isolated from the same plant seed by affinity chromatography, shows a primary specificity for N-acetyl-n-glucosamine. Several other N-acetyl-n-glucosamine binding lectins have been cited earlier. Wheat germ agglutinin isolated by Burger et al. (2) and Allen et al. (3) and the Ulex europeus lectin studied by Matsumoto and Osawa (4) are two examples. But this is the first instance of a lectin which displays a high activity towards a-linked N-acetyl-n-glucosaminyl units. In this communication we report our preliminary findings on the second lectin present in the seed extracts of B. simplicifolia, its purification by affinity chromatography and some of its properties. Materials and methods. Bandeiraea simplicifolia seeds were the generous gift of Calbiochem, La Jolla, California. Chitin used for affinity column was obtained from Pfanstiehl Laboratories, Waukegan, Illinois. BSA was obtained from Miles Laboratories, Kankakee, Illinois. Polyvinyl pyrrolidone was obtained from Calbiochem, La Jolla, California. All other chemicals used in this investigation were of reagent grade or the best quality available. Unless otherwise specified all experiments were conducted at 4°C. The sugars used in this study were available from previous studies or purchased from Pfanstiehl Laboratories, Waukegan, Illinois. The disaccharide 3-O-(2-acetamido-2-deoxy-cu-n-glucopyranosyl)-n-glucopyranose was kindly provided by Dr. R. U. Lemieux (51, University of Alberta, Canada. The p-azophenyl 2-acetamido-2-deoxy-(a and p)-n-glucopyranoside-BSA conjugates (a-GlcNAcBSA or p-GlcNAc-BSA) were prepared by the