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Updated: Aug 15, 2026

Förster Resonance Energy Transfer Mapping: A New Methodology to Elucidate Global Structural Features
Published on: March 16, 2022
Mapping the interaction of the STT3 subunit of the oligosaccharyl transferase complex with nascent polypeptide chains
Andrey L Karamyshev1, Daniel J Kelleher, Reid Gilmore
1Department of Medical Biochemistry and Genetics, Texas A&M University System Health Science Center, USA.
Abstract:
Many secretory and membrane proteins are N-glycosylated by the oligosaccharyl transferase complex during their translocation across the endoplasmic reticulum membrane. Several experimental observations suggest that the highly conserved STT3 subunit contains the active site of the oligosaccharyl transferase. Here, we report a detailed study of the interaction between the active site of the STT3 protein and nascent polypeptide chains using an in vitro photocrosslinking technique. Our results show that the addition of a glycan moiety in a stretch of approximately 15 residues surrounding a QK(*)T cross-linking site impairs the interaction between the nascent chain and STT3.
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