2I5K

Crystal structure of Ugp1p


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.1 Å
  • R-Value Free: 0.291 
  • R-Value Work: 0.226 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural Basis for Subunit Assembly in UDP-glucose Pyrophosphorylase from Saccharomyces cerevisiae

Roeben, A.Plitzko, J.M.Koerner, R.Boettcher, U.M.K.Siegers, K.Hayer-Hartl, M.Bracher, A.

(2006) J.Mol.Biol. 364: 551-560

  • DOI: 10.1016/j.jmb.2006.08.079

  • PubMed Abstract: 
  • UDP-glucose is the universal activated form of glucose, employed in all organisms for glucosyl transfer reactions and as precursor for various activated carbohydrates. In animal and fungal metabolism, UDP-glucose is required for utilization of galact ...

    UDP-glucose is the universal activated form of glucose, employed in all organisms for glucosyl transfer reactions and as precursor for various activated carbohydrates. In animal and fungal metabolism, UDP-glucose is required for utilization of galactose and for the synthesis of glycogen, the major carbohydrate storage polymer. The formation of UDP-glucose is catalyzed by UDP-glucose pyrophosphorylase (UGPase), which is highly conserved among eukaryotes. Here, we present the crystal structure of yeast UGPase, Ugp1p. Both in solution and in the crystal, Ugp1p forms homooctamers, which represent the enzymatically active form of the protein. Ugp1p subunits consist of three domains, with the active site presumably located in the central SpsA GnT I core (SGC) domain. The association in the octamer is mediated by contacts between left-handed beta-helices in the C-terminal domains, forming a toroidal solenoid structure in the core of the complex. The catalytic domains attached to this scaffold core do not directly contact each other, consistent with simple Michaelis-Menten kinetics found for Ugp1p. Conservation of hydrophobic residues at the subunit interfaces suggests that all fungal and animal homologs form this quarternary structure arrangement in contrast to monomeric plant UGPases, which have charged residues at these positions. Implications of this oligomeric arrangement for regulation of UGPase activity in fungi and animals are discussed.


    Organizational Affiliation

    Department of Cellular Biochemistry, Max-Planck-Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
UTP--glucose-1-phosphate uridylyltransferase
A, B
488Saccharomyces cerevisiae (strain ATCC 204508 / S288c)Mutation(s): 0 
Gene Names: UGP1
EC: 2.7.7.9
Find proteins for P32861 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Go to UniProtKB:  P32861
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.1 Å
  • R-Value Free: 0.291 
  • R-Value Work: 0.226 
  • Space Group: I 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 110.191α = 90.00
b = 147.437β = 90.00
c = 167.752γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
MOLREPphasing
CCP4data scaling
PDB_EXTRACTdata extraction
MOSFLMdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2006-11-28
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Advisory, Version format compliance