Functional neoglycopeptides: synthesis and characterization of a new class of MUC1 glycoprotein models having core 2-based O-glycan and complex-type N-glycan chains

Biochemistry. 2009 Nov 24;48(46):11117-33. doi: 10.1021/bi901557a.


An efficient protocol for the construction of MUC1-related glycopeptide analogues having complex O-glycan and N-glycan chains was established by integrating chemical and enzymatic approaches on the functional polymer platforms. We demonstrated the feasibility of sortase A-mediated ligation between two glycopeptide segments by tagging with signal peptides, LPKTGLR and GG, at each C- or N-terminal position. Structural analysis of the macromolecular N,O-glycopeptides was performed by means of ESI-TOFMS (MS/MS) equipped with an electron-captured dissociation device. Immunological assay using MUC1 glycopeptides synthesized in this study revealed that N-glycosylation near the antigenic O-glycosylated PDTR motif did not disturb the interaction between the anti-MUC1 monoclonal antibody and this crucial O-glycopeptide moiety. NMR study indicated that the N-terminal immunodominant region [Ala-Pro-Asp-Thr(O-glycan)-Arg] forms an inverse gamma-turn-like structure, while the C-terminal region composed of N-glycopeptide and linker SrtA-peptide was proved to be an independently random structure. These results indicate that the bulky O- and N-glycan chains can function independently as disease-relevant epitopes and ligands for carbohydrate-binding proteins, when both are combined by an artificial intervening peptide having a possible effect of separating N- and C-terminal regions. The present strategy will greatly facilitate rapid synthesis of multiply functionalized complex neoglycopeptides as new types of convenient tools or models for the investigation of thhe structure-function relationship of various glycoproteins and development of novel class glycopeptide-based biopharmaceuticals, drug delivery systems, and biomedical materials.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Aminoacyltransferases / chemistry
  • Antibodies, Monoclonal / immunology
  • Bacterial Proteins / chemistry
  • Binding, Competitive / immunology
  • Biocatalysis
  • Carbohydrate Sequence
  • Chromatography, High Pressure Liquid
  • Cysteine Endopeptidases / chemistry
  • Glycoproteins / biosynthesis
  • Glycoproteins / chemical synthesis
  • Glycoproteins / chemistry*
  • Glycoproteins / immunology
  • Humans
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Molecular Conformation
  • Molecular Sequence Data
  • Molecular Structure
  • Mucin-1 / biosynthesis
  • Mucin-1 / chemistry*
  • Mucin-1 / immunology
  • Polysaccharides / biosynthesis
  • Polysaccharides / chemical synthesis
  • Polysaccharides / chemistry*
  • Polysaccharides / immunology
  • Staphylococcus aureus / enzymology
  • Tandem Mass Spectrometry


  • Antibodies, Monoclonal
  • Bacterial Proteins
  • Glycoproteins
  • MUC1 protein, human
  • Mucin-1
  • Polysaccharides
  • Aminoacyltransferases
  • sortase A
  • Cysteine Endopeptidases