Identification of peanut agglutinin receptors on human erythrocyte ghosts by affinity crosslinking using a new cleavable heterobifunctional reagent

Peanut agglutinin was acylated with a new heterobifunctional, cleavable photosensitive crosslinking reagent, N-[4-(p-azidophenylazo)benzoyl]-3-aminopropyl-N′-oxysuccinimide ester. The lectin derivative binds specifically and reversibly to neuraminidase-treated human erythrocyte ghosts and upon irradiation covalent attachment of over 35% of the bound lectin occurs. The affinity-crosslinked ghosts were solublized in deoxycholate, immunoprecipitated with anti-peanut agglutinin antiserum, and analyzed by sodium dodecylsulfate polyacrylamine gel electrophoresis. Bands containing both peanut agglutinin and membrane glycoproteins were detected with apparent molecular weights of 58 000, 85 000, 110 000 and 135 000. Upon subsequent cleavage with sodium dithionite, asialoglycophorin A (apparent M.W. 41 000 and 85 000) and a second glycoprotein (apparent M.W. 58 000 - 61 000) were tentatively identified as the receptors for peanut agglutinin in the intact membrane.