Sialyl-Tn antigen expression and O-linked GalNAc-Thr synthesis by Trypanosoma cruzi

Biochem Biophys Res Commun. 2003 Dec 26;312(4):1309-16. doi: 10.1016/j.bbrc.2003.11.060.

Abstract

Most Trypanosoma cruzi O-glycans are linked to Thr/Ser residues via N-acetylglucosamine. We report that the mucin-type carcinoma-associated sialyl-Tn antigen (NeuAc-GalNAc-O-Ser/Thr) is expressed by T. cruzi. A specific MAb allowed us to localize the antigen on the surface of epimastigotes and to identify reactive components in parasite lysates (32, 60, and 94kDa). In addition, ppGalNAc-T activity was characterized in epimastigotes, and direct evidence was obtained for the in vitro incorporation of GalNAc to a synthetic peptide derived from a T. cruzi mucin. These results add an as yet unknown complexity to the pathways of O-glycan biosynthesis in this protozoan parasite.

Publication types

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

MeSH terms

  • Acetylgalactosamine / chemistry
  • Acetylgalactosamine / metabolism*
  • Amino Acid Sequence
  • Animals
  • Antigens, Tumor-Associated, Carbohydrate / chemistry
  • Antigens, Tumor-Associated, Carbohydrate / metabolism*
  • Enzyme Activation
  • Fluorescent Antibody Technique, Direct / methods
  • Hydrogen-Ion Concentration
  • Metalloendopeptidases
  • Molecular Sequence Data
  • Mucins / chemistry
  • Mucins / metabolism*
  • N-Acetylgalactosaminyltransferases / chemistry
  • N-Acetylgalactosaminyltransferases / metabolism*
  • Trypanosoma cruzi / chemistry
  • Trypanosoma cruzi / metabolism*

Substances

  • Antigens, Tumor-Associated, Carbohydrate
  • Mucins
  • Tn antigen
  • sialosyl-Tn antigen
  • N-Acetylgalactosaminyltransferases
  • UDP-GalNAc polypeptide N-acetylgalactosaminyltransferase 9
  • Metalloendopeptidases
  • molecule metalloprotease-related protein-1, human
  • Acetylgalactosamine