
%0 Journal Article
%A Baldo, BA 
%A Barnett, D 
%A Lee, JW 
%T Lectins as Cytochemical Probes of the Developing Wheat Grain. V. Demonstration of Separate Polysaccharides Containing N-Acetyl-D-Glucosamine and D-Galactose in Nuclear Epidermal Cell Walls
%J Functional Plant Biology
%D 1984/06/01
%V 11
%N 3
%P 179-190
%K 
%R https://doi.org/10.1071/PP9840179
%U https://www.publish.csiro.au/paper/PP9840179 
%X Fluorescein isothiocyanate-labelled lectin from wheat-gem, which binds N-acetyl-D-glucosamine, and Griffonia simplicifolia, Arachis hypogaea and Glycine max lectins, each of which binds D-galactose, react with nucellar epidermal cell walls in thin sections of plastic-embedded developing wheat grain. Reactivity of these cell walls with periodic acid-Schiff reagent, the absence of staining with protein stains and the failure of a number of proteases and the endoglycosidases D and H to prevent the binding suggested that the lectin-reactive wall components are neither proteins nor N-glycosidically linked glycoproteins. Morphological differences in lectin staining patterns and treatment of sections with chitinase and &#945;-galactosidase, prior to the reaction with the lectins, indicated that two separate polysaccharides are probably involved in the binding. Chitinase removed the reactivity of the nucellar epidermal cell walls for wheat-germ lectin but the binding of D-galactose-specific lectins was unimpaired. Conversely, &#945;-galactosidase did not affect the binding of wheat-germ lectin but reactivity with the galactose-specific lectins was abolished. From the available evidence we conclude that one polysaccharide in the nucellar epidermal cell wall reacts with wheat-germ lectin and contains N-acetyl-D-glucosamine in a chitin-like structure. The other polysaccharide reacts with D-galactose- specific lectins by virtue of terminal &#945;-D-galactose residues. Hydrolysis and subsequent chromatographic analysis of nucellar epidermal cell walls peeled from immature grains revealed the presence of D-glucosamine, D-glucose, D-galactose, D-xylose, L-arabinose and a trace of D-mannose. 
