Reaction of Some Invertebrate and Plant Agglutinins and a Mouse Myeloma Anti-Galactan Protein With an Arabinogalactan From Wheat

Abstract

Plant, invertebrate and vertebrate proteins which show anti-galactan combining specificities were used in precipitation and inhibition studies with arabinogalactan preparations from wheat and ryegrass (Lolium multiflorum). Of the agglutinins studied, only mouse anti-galactan myeloma protein J539 showed strong reactivity with wheat arabinoglactan-peptide. Weak reactions were observed with the agglutinins from the clam Tridacna maxima, the sponge Axinella polypoides and the anemone Cerianthus membranaceus. No reactions were detected with lectins from the plants Abrus precatorius and Ricinus communis. Reactions readily occurred between Lolium arabinogalactan-protein and the invertebrate and vertebrate agglutinins. Removal of terminal arabinosyl residues from the wheat and Lotium arabinogalactans either by mild acid hydrolysis or by treatment with an arabinofuranosidase increased the reactivity of both peptidoglycans with all of the agglutinins examined except the Ricinus RCAl lectin. Results obtained with wheat arabinogalactan indicate that few D-galactose units are terminal and available for reaction. The difference in reactivities between the wheat and Lotium arabinogalactans may be due to the differences in the galactose:arabinose ratios or to differences in linkage of the galactosyl residues on the two peptidoglycans, or both. Results indicate that the mouse anti-galactan could be a useful reagent for the subcellular localization of wheat arabinogalactan and that tridacnin and Axinella agglutinins could be used to localize the arabinogalactan in L. multiflorum cells.