Abstract
The tissue structure of the aleurone layer in different bean seeds, and its content of the glycine-rich protein (GRP) were investigated. The aleurone layers of soybean (Glycine max, cv. Enrei), black soybean (Glycine max, cv. Tanbaguro), and wild soybean (Glycine soja) were thicker compared to those of red kidney bean (Phaseolus vulgaris, cv. Taishokintoki) and marbled kidney bean (Phaseolus vulgaris, cv. Toramame). The soybean GRP, which is a characteristic of the cell walls in the aleurone layer, was found mainly in the pectin fraction. The GRP content, found in the hot-water-soluble fraction of the aleurone layer, in the three kinds of soybean was greater than that found in the two kinds of kidney bean. The estimated molecular size (about 30 kDa) of the GRPs extracted from both the wild and black soybeans was the same as that from Glycine max, cv Enrei. The GRP, found in the aleurone layer of plantS belonging to the soybean genus, probably has some role in strengthening the cell walls in this tissue.
