Multivalent Galacto-trehaloses: Design, Synthesis, and Biological Evaluation under the Concept of Carbohydrate Modules

Abstract

Galacto-trehalose (GT) is a novel class of 1,1'-linked nonreducing disaccharide having an α-galactoside epitope. In this study, a pair of α,α- and α,β-GT isomers were prepared in one pot with our α-glycosylation method, converted into vinyl monomers and then subjected to radical copolymerization with a second sugar (4-acrylamidophemyl β-Glc or β-GlcNAc) in the presence of acrylamide. The derived glycopolymers were assayed with α-galactoside-specific proteins (BSI-B(4) lectin and Shiga toxin-1) to show the results that both α,α- and α,β-isomers are recognized by these carbohydrate-binding proteins more strongly in forms of the GT polymers. Moreover, the glycopolymer carrying both α,α-GT and β-GlcNAc along the polymer chain showed an integrated detoxifying activity to the E. coli toxin as the result of a "module effect" of the second sugar.