Methylation analysis of cell-wall material from parenchymatous tissues of phaseolus vulgaris and phaseolus coccineus

Abstract

Cell-wall material (CWM) from parenchymatous tissues of pods of dwarf french and runner beans was prepared by sequentially extracting the wet ball-milled tissues with 1% aqueous sodium deoxycholate, phenol-acetic acid-water, and 90% aqueous dimethyl sulphoxide. The overall monosaccharide compositions of the preparations were similar, and each contained small but significant amounts of hydroxyprolinerich glycoproteins. Methylation analysis of the CWM revealed the following main glycosidic linkages in descending order of concentration: 4-linked galacturonic acid, 4-linked glucose, 4-linked galactose, 5-linked arabinose, 2-linked rhamnose, and 4-linked xylose. The major branch-points were those through C-6 of glucose, C-3 of arabinose, and C-4 of rhamnose. Arabinose, xylose, and galactose constituted the non-reducing end-groups. The general structural features of the CWM are discussed.