Synthesis of undecaprenyl pyrophosphate-linked glycans as donor substrates for bacterial protein N-glycosylation
摘要:
Synthesis of undecaprenyl pyrophosphate (Und-PP)-linked glycans is described. Bacterial ([E](3),[Z](7))-undecaprenol was synthesized from trans-geranylgeranyl sulfone and isoprenoid building blocks, which was converted to undecaprenyl phosphate (Und-P). It was coupled with glycosyl phosphates to afford Und-PP-linked glycans, including core trisaccharide of Campylobacter jejuni N-glycan. Our synthetic method for Und-PP-linked glycan would provide various substrates as a useful tool for systematic analysis of bacterial protein N-glycosylation. (C) 2009 Elsevier Ltd. All rights reserved.
Synthesis of N-linked glycan derived from Gram-negative bacterium, Campylobacter jejuni
摘要:
Recent research has revealed the presence of asparagine (Asn)-linked (N-linked) glycoproteins in certain prokaryotes. In this paper, we describe the chemical synthesis of a novel N-glycan derived from Campylobacter jejuni, a heptasaccharide composed of Asn-linked bacillosamine (Bac), repeating GalNAc, and branching Glc, namely GalNAc-alpha(1,4)-GalNAc-alpha(1,4)-[Glc-beta(1,3)-] GalNAc-alpha(1,4)-GalNAc-alpha(1,4)-GalNAc-alpha(1,3)-Bac. The synthesis started from a Bac-acceptor, which was consecutively glycosylated with 4-O-pentafluoropropionyl (PFP) protected donors to give heptasaccharide. Reduction of azide groups was followed by debenzylation to complete the synthesis of the target oligosaccharide. (c) 2007 Elsevier Ltd. All rights reserved.