Investigating asparagine-linked protein glycosylation in eukaryotic and prokaryotic systems

N-linked protein glycosylation is characterized by the formation of a -glycosylamine linkage to an asparagine residue within the Asn-Xaa-Ser/Thr consensus sequence. This modification is found in organisms from eukaryotic, archaeal and bacterial domains and is implicated in numerous cellular processes. Recently, a system of N-linked glycosylation was characterized in a gram-negative bacterium, Campylobacter jejuni. Glycosylation in this organism involves the transfer of a heptasaccharide from an undecaprenyl-pyrophosphate (Und-PP) carrier onto the asparagine side-chain of a protein. The genes in the 'pgl gene cluster' encode all of the proteins necessary for the biosynthesis of the glycan donor and its ultimate transfer to protein. The heptasaccharide donor has been characterized as GalNAc-al,4- GalNAc-al,4-(Glcpl1,3)-GalNAc-al,4-GalNAc-al,4-GalNAc-al,3-Bac-al ,PP-Und, where Bac is bacillosamine (2,4-diacetamido-2,4,6-trideoxyglucose). A synthetic route was developed to access bacillosamine-phosphate, which was incorporated into UDP-bacillosamine (UDP-Bac) and undecaprenyl-pyrophosphate-bacillosamine (Und-PP-Bac), which are substrates for the Pgl enzymes. Using the synthetic UDP-Bac, the role of the PglC glycophosphoryltransferase was elucidated in vitro.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Chemistry.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2006

Author dc:creator

• Weerapana, Eranthie

Advisor dc:contributor.advisor

• Barbara Imperiali.

• Chemistry.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/34495
• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Identifier URI

http://dspace.mit.edu/handle/1721.1/34495

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/34495