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Glyco-Engineering of Plant-Based Expression Systems

  • Rainer Fischer
  • Tanja Holland
  • Markus Sack
  • Stefan Schillberg
  • Eva Stoger
  • Richard M. Twyman
  • Johannes F. Buyel
Chapter
Part of the Advances in Biochemical Engineering/Biotechnology book series

Abstract

Most secreted proteins in eukaryotes are glycosylated, and after a number of common biosynthesis steps the glycan structures mature in a species-dependent manner. Therefore, human therapeutic proteins produced in plants often carry plant-like rather than human-like glycans, which can affect protein stability, biological function, and immunogenicity. The glyco-engineering of plant-based expression systems began as a strategy to eliminate plant-like glycans and produce human proteins with authentic or at least compatible glycan structures. The precise replication of human glycans is challenging, owing to the absence of a pathway in plants for the synthesis of sialylated proteins and the necessary precursors, but this can now be achieved by the coordinated expression of multiple human enzymes. Although the research community has focused on the removal of plant glycans and their replacement with human counterparts, the presence of plant glycans on proteins can also provide benefits, such as boosting the immunogenicity of some vaccines, facilitating the interaction between therapeutic proteins and their receptors, and increasing the efficacy of antibody effector functions.

Graphical Abstract

Typical structures of native mammalian and plant glycans with symbols indicating sugar residues identified by their short form and single-letter codes. Both glycans contain fucose, albeit with different linkages

Keywords

Glycan Glycoprotein Glycotransferase N-linked O-linked Pharmaceutical protein Recombinant protein Transgenic plant Transient expression 

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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Rainer Fischer
    • 1
    • 2
  • Tanja Holland
    • 2
    • 3
  • Markus Sack
    • 2
    • 4
  • Stefan Schillberg
    • 5
  • Eva Stoger
    • 6
  • Richard M. Twyman
    • 7
  • Johannes F. Buyel
    • 2
    • 5
  1. 1.Indiana Biosciences Research InstituteIndianapolisUSA
  2. 2.Institute for Molecular Biotechnology, RWTH Aachen UniversityAachenGermany
  3. 3.Eppendorf AG, Bioprocess CenterJuelichGermany
  4. 4.Pro-SPR GmbHAlsdorfGermany
  5. 5.Fraunhofer Institute for Molecular Biology and Applied Ecology IMEAachenGermany
  6. 6.Department of Applied Genetics and Cell BiologyUniversity of Natural Resources and Life SciencesViennaAustria
  7. 7.TRM LtdYorkUK

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