Conformational analysis of a glycosylated human myelin oligodendrocyte glycoprotein peptide epitope able to detect antibody response in multiple sclerosis

J Med Chem. 2001 Jul 5;44(14):2378-81. doi: 10.1021/jm010811t.

Abstract

Myelin oligodendrocyte glycoprotein (MOG), a minor myelin component, is an important central nervous system specific target autoantigen for primary demyelination in autoimmune diseases such as multiple sclerosis (MS). The native structure of MOG presents a glycosylation site at position 31 (Asn(31)). It has been recently described that glycosylation of a MOG peptide epitope improved the detection of specific autoantibodies in sera of MS patients. The solution conformational behavior of two MOG derived peptides-hMOG(30-50) (1) and the glycosylated analogue [Asn(31)(N-beta-Glc)]hMOG(30-50) (2)-were investigated through NMR analysis in a water/HFA solution. Conformational studies revealed that peptides 1 and 2 adopted similar conformations in this environment. In particular, they showed strong propensity to assume a well-defined amphipatic structure encompassing residues 41-48. The N-terminal region resulted to be almost completely unstructured for both peptides. The presence in 1 of a low populated Asx-turn conformation characteristic of the Asn-Xaa-Thr glycosylation sites was the only conformational difference between peptides 1 and 2. Thus, the specific antibody recognition of peptide 2 is most likely driven by direct interactions of the antibody binding site with the Asn-linked sugar moiety.

MeSH terms

  • Amino Acid Sequence
  • Antigens, Surface / chemistry*
  • Autoantibodies / analysis*
  • Autoantigens / chemistry*
  • Epitopes
  • Glycosylation
  • Humans
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Molecular Sequence Data
  • Multiple Sclerosis / immunology*
  • Myelin Proteins
  • Myelin-Associated Glycoprotein / chemistry*
  • Myelin-Oligodendrocyte Glycoprotein
  • Oligodendroglia / chemistry*
  • Protein Conformation

Substances

  • Antigens, Surface
  • Autoantibodies
  • Autoantigens
  • Epitopes
  • MOG protein, human
  • Myelin Proteins
  • Myelin-Associated Glycoprotein
  • Myelin-Oligodendrocyte Glycoprotein