Synthesis of major histocompatibility complex class I binding glycopeptides

Abstract

Four Major Histocompatibility Complex (MHC) Class I binding glycopeptides and two peptide analogues, from a cytotoxic T-lymphocyte (CTL) epitope of Sendai Virus Nucleoprotein, have been prepared using solid-phase peptide synthesis employing the following glycosyl amino acid building blocks: FmocSer(Ac₃-β-D-GlcNAc)OH 1, FmocSer(Ac₃-α-D-GalN₃)OPfp 2, FmocAsn(Ac₃-β-D-GlcNAc)OH 3 and FmocAsn(Ac₃-β-D-GalNAc)OH 4. Previously, we examined the influence of glycosylation on peptide binding to the MHC Class I molecule and CTL recognition of these peptides. The synthesis and characterization of compounds 1–4 as well as the resulting glycopeptides is described. In addition, results of NMR investigations demonstrating that peptide K3, and glycopeptides K3-O-GlcNAc and K3-O-GalNAc, show two distinct conformations in solution as a result of cis–trans isomerization about a Tyr-Pro amide bond are reported.