N-glycosylation engineering of plants for the biosynthesis of glycoproteins with bisected and branched complex N-glycans

Glycobiology. 2011 Jun;21(6):813-23. doi: 10.1093/glycob/cwr009. Epub 2011 Feb 11.

Abstract

Glycoengineering is increasingly being recognized as a powerful tool to generate recombinant glycoproteins with a customized N-glycosylation pattern. Here, we demonstrate the modulation of the plant glycosylation pathway toward the formation of human-type bisected and branched complex N-glycans. Glycoengineered Nicotiana benthamiana lacking plant-specific N-glycosylation (i.e. β1,2-xylose and core α1,3-fucose) was used to transiently express human erythropoietin (hEPO) and human transferrin (hTF) together with modified versions of human β1,4-mannosyl-β1,4-N-acetylglucosaminyltransferase (GnTIII), α1,3-mannosyl-β1,4-N-acetylglucosaminyltransferase (GnTIV) and α1,6-mannosyl-β1,6-N-acetylglucosaminyltransferase (GnTV). hEPO was expressed as a fusion to the IgG-Fc domain (EPO-Fc) and purified via protein A affinity chromatography. Recombinant hTF was isolated from the intracellular fluid of infiltrated plant leaves. Mass spectrometry-based N-glycan analysis of hEPO and hTF revealed the quantitative formation of bisected (GnGnbi) and tri- as well as tetraantennary complex N-glycans (Gn[GnGn], [GnGn]Gn and [GnGn][GnGn]). Co-expression of GnTIII together with GnTIV and GnTV resulted in the efficient generation of bisected tetraantennary complex N-glycans. Our results show the generation of recombinant proteins with human-type N-glycosylation at great uniformity. The strategy described here provides a robust and straightforward method for producing mammalian-type N-linked glycans of defined structures on recombinant glycoproteins, which can advance glycoprotein research and accelerate the development of protein-based therapeutics.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Erythropoietin / biosynthesis*
  • Erythropoietin / chemistry
  • Erythropoietin / isolation & purification
  • Glycosylation
  • Humans
  • Nicotiana / chemistry
  • Nicotiana / metabolism*
  • Plant Leaves / chemistry
  • Plant Leaves / metabolism*
  • Polysaccharides / chemistry
  • Polysaccharides / metabolism*
  • Protein Engineering
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / isolation & purification
  • Transferrin / biosynthesis*
  • Transferrin / chemistry
  • Transferrin / isolation & purification

Substances

  • EPO protein, human
  • Polysaccharides
  • Recombinant Proteins
  • Transferrin
  • Erythropoietin