P39007: Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3 (STT3)

Dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit STT3 (STT3) is a 718-residue protein from Saccharomyces cerevisiae (strain ATCC 204508 / S288c). This is its AlphaFold structure prediction, created 1 Aug 2025. UniProt accession: P39007.

Gene
STT3
Organism
Saccharomyces cerevisiae (strain ATCC 204508 / S288c)
Length
718 residues
Mean pLDDT
88.9
Model
AF-P39007-F1 v6
Model created
1 Aug 2025
PDB structures
7

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Model confidence (pLDDT)

The mean pLDDT of this model is 88.9 (confident overall). pLDDT is AlphaFold's per-residue confidence score from 0 to 100. In MolViewer, choose the B-factor color scheme to color the model by pLDDT, because AlphaFold stores it in the B-factor column.

pLDDT bandMeaningShare of residues
Above 90Very high: backbone and side chains are usually accurate65%
70 to 90Confident: backbone generally right30%
50 to 70Low: treat with caution2%
Below 50Very low: often disordered regions3%

What pLDDT means and how to read it

Function

Catalytic subunit of the oligosaccharyl transferase (OST) complex that catalyzes the initial transfer of a defined glycan (Glc(3)Man(9)GlcNAc(2) in eukaryotes) from the lipid carrier dolichol-pyrophosphate to an asparagine residue within an Asn-X-Ser/Thr consensus motif in nascent polypeptide chains, the first step in protein N-glycosylation. N-glycosylation occurs cotranslationally and the complex associates with the Sec61 complex at the channel-forming translocon complex that mediates protein translocation across the endoplasmic reticulum (ER). All subunits are required for a maximal enzyme activity (PubMed:12359722). This subunit contains the active site and the acceptor peptide and…

Subunit structure

Component of the oligosaccharyltransferase (OST) complex, which appears to exist in two assemblies comprising OST1, OST2, OST4, OST5, STT3, SWP1, WPB1, and either OST3 or OST6 (PubMed:10677492, PubMed:15831493, PubMed:15886282, PubMed:16096345, PubMed:16297388, PubMed:29301962, PubMed:9405463, PubMed:9435788). OST assembly occurs through the formation of 3 subcomplexes. Subcomplex 1 contains…

Subcellular location

Endoplasmic reticulum membrane

Experimental structures in the PDB

Compare the prediction with experimentally determined structures of the same protein:

PDB IDMethodResolutionChains and residues
8AGEEM2.8 ÅA=1-718
8AGBEM3.0 ÅA=1-718
8AGCEM3.1 ÅA=1-718
6EZNEM3.3 ÅF=1-718
7OCIEM3.46 ÅF=1-718
6C26EM3.5 ÅA=1-718
2LGZNMRA=465-718

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