Exploring the substrate specificity of sialyltransferases

Abstract

Twelve trisaccharide derivatives designed for detailed exploration of the acceptor specificity of sialyltransferases involved in the biosynthesis of N-glycans have been synthesized. These compounds include β-D-Galp-(1-4)-β-D-GlcpNAc-(1-2)-α-D-Manp-(1-O)(CH 2)7CH3 and analogues containing structural variants of D-galactose. All trisaccharides were obtained by condensation of suitably modified glycosyl donors with a single disaccharide acceptor, thus limitating the number of reaction steps required. After deprotection, the compounds were employed to delineate the recognition characteristics of several natural and recombinant sialyltransferases.