1RKL

NMR structure of yeast oligosaccharyltransferase subunit Ost4p


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 500 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural basis for the function of a minimembrane protein subunit of yeast oligosaccharyltransferase

Zubkov, S.Lennarz, W.J.Mohanty, S.

(2004) Proc.Natl.Acad.Sci.USA 101: 3821-3826

  • DOI: 10.1073/pnas.0400512101

  • PubMed Abstract: 
  • N-glycosylation of proteins is an essential, highly conserved modification reaction that occurs in all eukaryotes and some prokaryotes. This process is catalyzed by oligosaccharyltransferase (OT), a multisubunit enzyme localized in the endoplasmic re ...

    N-glycosylation of proteins is an essential, highly conserved modification reaction that occurs in all eukaryotes and some prokaryotes. This process is catalyzed by oligosaccharyltransferase (OT), a multisubunit enzyme localized in the endoplasmic reticulum. Complete loss of N-glycosylation is lethal in all organisms. In Saccharomyces cerevisiae, OT is composed of nine nonidentical membrane proteins. Here, we report the atomic structure of an OT subunit from S. cerevisiae, Ost4p. This unusually small membrane protein containing only 36 residues folds into a well formed, kinked helix in the model-membrane solvent system used in this study. The residues critical for the OT activity and the stability of Stt3p-Ost4p-Ost3p subcomplex are located in helix alpha2, the larger cytosolic half of this kinked helix. The residues known to disrupt Ost4p-Stt3p complex form a well defined ridge in the 3D structure. Taking together prior mutational studies and the NMR structure of Ost4p, we propose that in the OT complex Stt3p is packed against the alpha 2-helix of Ost4p by using a "ridges-into-grooves" model, with Met-18, Leu-21, and Ile-24 as the packing interface on one face, whereas Ost3p is involved in interactions with Met-19, Thr-20, Ile-22, and Val-23 on the other face.


    Organizational Affiliation

    Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Dolichyl-diphosphooligosaccharide--protein glycosyltransferase 4 kDa subunit
A
36Saccharomyces cerevisiae (strain ATCC 204508 / S288c)Mutation(s): 0 
Gene Names: OST4
Find proteins for Q99380 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Go to Gene View: OST4
Go to UniProtKB:  Q99380
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 500 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 1RKL Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-03-23
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance