6P28

Crystal structure of the MIR domain (aa 337-532) of the S. cerevisiae mannosyltransferase Pmt2


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.35 Å
  • R-Value Free: 0.213 
  • R-Value Work: 0.187 
  • R-Value Observed: 0.187 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structure of the eukaryotic protein O-mannosyltransferase Pmt1-Pmt2 complex.

Bai, L.Kovach, A.You, Q.Kenny, A.Li, H.

(2019) Nat Struct Mol Biol 26: 704-711

  • DOI: 10.1038/s41594-019-0262-6
  • Primary Citation of Related Structures:  
    6P25, 6P28, 6P2R

  • PubMed Abstract: 
  • In eukaryotes, a nascent peptide entering the endoplasmic reticulum (ER) is scanned by two Sec61 translocon-associated large membrane machines for protein N-glycosylation and protein O-mannosylation, respectively. While the structure of the eight-protein oligosaccharyltransferase complex has been determined recently, the structures of mannosyltransferases of the PMT family, which are an integral part of ER protein homeostasis, are still unknown ...

    In eukaryotes, a nascent peptide entering the endoplasmic reticulum (ER) is scanned by two Sec61 translocon-associated large membrane machines for protein N-glycosylation and protein O-mannosylation, respectively. While the structure of the eight-protein oligosaccharyltransferase complex has been determined recently, the structures of mannosyltransferases of the PMT family, which are an integral part of ER protein homeostasis, are still unknown. Here we report cryo-EM structures of the Saccharomyces cerevisiae Pmt1-Pmt2 complex bound to a donor and an acceptor peptide at 3.2-Å resolution, showing that each subunit contains 11 transmembrane helices and a lumenal β-trefoil fold termed the MIR domain. The structures reveal the substrate recognition model and confirm an inverting mannosyl-transferring reaction mechanism by the enzyme complex. Furthermore, we found that the transmembrane domains of Pmt1 and Pmt2 share a structural fold with the catalytic subunits of oligosaccharyltransferases, confirming a previously proposed evolutionary relationship between protein O-mannosylation and protein N-glycosylation.


    Organizational Affiliation

    Structural Biology Program, Van Andel Research Institute, Grand Rapids, MI, USA. Huilin.Li@vai.org.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Dolichyl-phosphate-mannose--protein mannosyltransferase 2A196Saccharomyces cerevisiaeMutation(s): 0 
Gene Names: PMT2FUN25YAL023C
EC: 2.4.1.109
Membrane Entity: Yes 
UniProt
Find proteins for P31382 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Explore P31382 
Go to UniProtKB:  P31382
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP31382
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.35 Å
  • R-Value Free: 0.213 
  • R-Value Work: 0.187 
  • R-Value Observed: 0.187 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 34.289α = 90
b = 71.403β = 96.37
c = 37.886γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data reduction
SCALAdata scaling
PHASERphasing

Structure Validation

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Entry History & Funding Information

Deposition Data

  • Released Date: 2019-07-10 
  • Deposition Author(s): Bai, L., Li, H.

Funding OrganizationLocationGrant Number
National Institutes of Health/National Cancer Institute (NIH/NCI)United StatesR01-CA231466

Revision History  (Full details and data files)

  • Version 1.0: 2019-07-10
    Type: Initial release
  • Version 1.1: 2019-07-24
    Changes: Data collection, Database references
  • Version 1.2: 2019-08-21
    Changes: Data collection, Database references
  • Version 1.3: 2019-12-04
    Changes: Author supporting evidence