A new trisaccharide sugar chain linked to a serine residue in the first EGF-like domain of clotting factors VII and IX and protein Z

Adv Exp Med Biol. 1990:281:121-31. doi: 10.1007/978-1-4615-3806-6_12.

Abstract

Recently, we determined the complete amino acid sequence of bovine factor VII (Takeya, H. et al. (1988) J. Biol. Chem. 263, 14868-14877). In the course of the studies, we found an unknown serine derivative at position 52 in the first epidermal growth factor-like domain of factor VII. A pentapeptide isolated from the S-aminoethylated factor VII contained Ser-52, which could not be identified with a gas-phase sequencer. The same results were also obtained for a pentapeptide containing Ser-53 of factor IX and protein Z. Component sugar analysis revealed that the peptide contained 1 mol of glucose and 2 mol of xylose. This sugar component was also confirmed by high-resolution fast atom bombardment mass spectrometric analysis of the pentapeptide. The trisaccharide was released from the peptides by means of beta-elimination reaction and its reducing end was identified as pyridylamino-glucose. These results indicate the existence of a (Xyl2)Glc-Ser structure in factors VII, IX and protein Z. Similar results were obtained for human factors VII, IX and protein Z. This is the first report of a (Xyl2)-Glc-Ser structure in glycoproteins to our knowledge. The presence of the unique trisaccharide structure in factors VII, IX and protein Z leads us to anticipate its biological role in the tissue factor pathway.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Blood Proteins / chemistry*
  • Carbohydrate Sequence
  • Cattle
  • Chromatography, High Pressure Liquid
  • Epidermal Growth Factor / chemistry*
  • Factor IX / chemistry*
  • Factor VII / chemistry*
  • Humans
  • Models, Structural
  • Molecular Sequence Data
  • Oligosaccharides / chemistry
  • Oligosaccharides / isolation & purification*
  • Peptide Fragments / isolation & purification
  • Protein Conformation
  • Sequence Homology, Nucleic Acid
  • Serine*
  • Spectrometry, Mass, Fast Atom Bombardment

Substances

  • Blood Proteins
  • Oligosaccharides
  • Peptide Fragments
  • plasma protein Z
  • Serine
  • Epidermal Growth Factor
  • Factor VII
  • Factor IX