Design and Synthesis of Glycosylated Cholera Toxin B Subunit as a Tracer of Glycoprotein Trafficking in Organelles of Living Cells

Chemistry. 2022 Jul 1;28(37):e202201253. doi: 10.1002/chem.202201253. Epub 2022 May 23.

Abstract

Glycosylation of proteins is known to be essential for changing biological activity and stability of glycoproteins on the cell surfaces and in body fluids. Delivering of homogeneous glycoproteins into the endoplasmic reticulum (ER) and the Golgi apparatus would enable us to investigate the function of asparagine-linked (N-) glycans in the organelles. In this work, we designed and synthesized an intentionally glycosylated cholera toxin B-subunit (CTB) to be transported to the organelles of mammalian cells. The heptasaccharide, the intermediate structure of various complex-type N-glycans, was introduced to the CTB. The synthesized monomeric glycosyl-CTB successfully entered mammalian cells and was transported to the Golgi and the ER, suggesting the potential use of synthetic CTB to deliver and investigate the functions of homogeneous N-glycans in specific organelles of living cells.

Keywords: N-glycan; cholera toxin; glycoprotein; live imaging; native chemical ligation.

MeSH terms

  • Animals
  • Cholera Toxin* / metabolism
  • Endoplasmic Reticulum / metabolism
  • Glycoproteins* / chemistry
  • Glycosylation
  • Mammals / metabolism
  • Polysaccharides / chemistry

Substances

  • Glycoproteins
  • Polysaccharides
  • Cholera Toxin