Study on the structures of xyloglucans using xyloglucan specific enzymes

Xyloglucan is a major structural polysaccharide of the primary cell-walls of all higher plants. The xyloglucans from Gramineae and Solanaceae have more unsubstituted glucose residues compared to those from most dicotyledonous plants. A purified Penicillium sp. M451 or Geotrichum sp. M128 xyloglucan specific endo-1,4-beta-D-glucanase, a purified oligoxyloglucan-specific glycosidase, oligoxyloglucan reducing end-specific cellobiohydrolase from Geotrichum sp. M 128, and a purified isoprimeverose-producing oligoxyloglucan hydrolase from Eupenicillium sp, M9 are very useful for investigating the arrangement of the glucose residues which are not xylosylated at 0-6 in the beta-1,4-D-glucan backbone of Gramineae and Solanaceae xyloglucans. In this review, we summarize the structural study of xyloglucans from Gramineae and Solanaceae in addition to those from most dicotyledonous plants by xyloglucan specific enzymes.