DIVERGENT CHEMOENZYMATIC SYNTHESIS OF SHIGELLA FLEXNERI PENTASACCHARIDES FOR VACCINE DEVELOPMENT

摘要

Enteroinvasive gram-negative bacteria from the Shigella flexneri (SF) species are of particular concern and a prime target for vaccine development [1]. Most SF serotypes exhibit closely related O-antigens (O-Ag) that are a main target of protection against reinfection. SF O-Ag backbones of interest comprise a unique repeating unit made of four residues (ABCD). Serotype specificity is determined by site-selective O-acetylation and α-D-glucosylation (E) (Fig. 1) [2]. The chemo-enzymatic conception of glycobricks, easy-to-assemble into biologically active molecules mimicking the O-Ag from various serotypes, is the keystone of an ongoing strategy to a synthetic carbohydrate-based Shigella vaccine