STRUCTURAL FEATURES OF WATER-SOLUBLE PECTINS FROM MUNG BEAN HYPOCOTYLS

Physicochemical and enzymic approaches were used to characterize highly methylated pectins isolated from mung bean hypocotyl cell walls. Young cell walls were particularly rich in rhamnogalacturonan-1-like polysaccharides, the galacturonic units of which might be fully methylated. Short, smooth, homogalacturonan blocks separated these hairy regions. The homogalacturonans included acidic and highly methylated blocks, the structures of which have been investigated through computer simulations. Such complex carbohydrates were also detected in the older parts of the hypocotyls but to a lesser extent. Mature cells were characterized by the presence of pure, sparsely methylated homogalacturonan with randomly distributed methyl groups.