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Targeting Cysteine Thiols for in Vitro Site-specific Glycosylation of Recombinant Proteins
Published on: October 4, 2017
An evolving view of the eukaryotic oligosaccharyltransferase
Daniel J Kelleher1, Reid Gilmore
1Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605-2324, USA.
Glycobiology
|December 1, 2005
Summary
Oligosaccharyltransferase (OST) is crucial for N-linked glycosylation in eukaryotes. This review details OST structure, function, and evolution, highlighting the STT3 subunit
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Biology
Background:
- Asparagine-linked glycosylation (ALG) is a vital post-translational modification in eukaryotic cells.
- Many proteins entering the rough endoplasmic reticulum (RER) undergo N-linked glycosylation.
- Congenital disorders of glycosylation (CDG) are a group of human diseases linked to glycosylation defects.
Purpose of the Study:
- To review the structure and function of eukaryotic oligosaccharyltransferase (OST).
- To analyze archaebacterial and eubacterial OST homologues for insights into substrate recognition.
- To discuss the evolution and assembly of eukaryotic OST based on genomic evidence.
Main Methods:
- Comparative analysis of OST homologues across different domains of life.
- Review of recent genomic and biochemical findings on OST subunit composition.
- Examination of the role of the STT3 subunit in OST catalytic activity.
Main Results:
- Eukaryotic OST is a complex hetero-oligomeric enzyme with seven or eight subunits.
- The STT3 subunit is essential for the catalytic activity of OST.
- Analysis of OST homologues provides insights into donor and acceptor substrate recognition.
Conclusions:
- Understanding OST structure and function is critical for deciphering N-linked glycosylation pathways.
- The STT3 subunit plays a pivotal role in OST catalysis.
- Genomic evidence illuminates the evolutionary trajectory and subunit composition of eukaryotic OST.
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