3BRK

Crystal Structure of ADP-Glucose Pyrophosphorylase from Agrobacterium tumefaciens


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.221 
  • R-Value Observed: 0.225 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structural analysis of ADP-glucose pyrophosphorylase from the bacterium Agrobacterium tumefaciens.

Cupp-Vickery, J.R.Igarashi, R.Y.Perez, M.Poland, M.Meyer, C.R.

(2008) Biochemistry 47: 4439-4451

  • DOI: 10.1021/bi701933q
  • Primary Citation of Related Structures:  
    3BRK

  • PubMed Abstract: 
  • ADP-glucose pyrophosphorylase (ADPGlc PPase) catalyzes the conversion of glucose 1-phosphate and ATP to ADP-glucose and pyrophosphate. As a key step in glucan synthesis, the ADPGlc PPases are highly regulated by allosteric activators and inhibitors in accord with the carbon metabolism pathways of the organism ...

    ADP-glucose pyrophosphorylase (ADPGlc PPase) catalyzes the conversion of glucose 1-phosphate and ATP to ADP-glucose and pyrophosphate. As a key step in glucan synthesis, the ADPGlc PPases are highly regulated by allosteric activators and inhibitors in accord with the carbon metabolism pathways of the organism. Crystals of Agrobacterium tumefaciens ADPGlc PPase were obtained using lithium sulfate as a precipitant. A complete anomalous selenomethionyl derivative X-ray diffraction data set was collected with unit cell dimensions a = 85.38 A, b = 93.79 A, and c = 140.29 A (alpha = beta = gamma = 90 degrees ) and space group I 222. The A. tumefaciens ADPGlc PPase model was refined to 2.1 A with an R factor = 22% and R free = 26.6%. The model consists of two domains: an N-terminal alphabetaalpha sandwich and a C-terminal parallel beta-helix. ATP and glucose 1-phosphate were successfully modeled in the proposed active site, and site-directed mutagenesis of conserved glycines in this region (G20, G21, and G23) resulted in substantial loss of activity. The interface between the N- and the C-terminal domains harbors a strong sulfate-binding site, and kinetic studies revealed that sulfate is a competitive inhibitor for the allosteric activator fructose 6-phosphate. These results suggest that the interface between the N- and C-terminal domains binds the allosteric regulator, and fructose 6-phosphate was modeled into this region. The A. tumefaciens ADPGlc PPase/fructose 6-phosphate structural model along with sequence alignment analysis was used to design mutagenesis experiments to expand the activator specificity to include fructose 1,6-bisphosphate. The H379R and H379K enzymes were found to be activated by fructose 1,6-bisphosphate.


    Organizational Affiliation

    Department of Physiology and Biophysics, University of California, Irvine, California 92697, USA. jvickery@uci.edu



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Glucose-1-phosphate adenylyltransferaseX420Agrobacterium tumefaciensMutation(s): 0 
Gene Names: glgC
EC: 2.7.7.27
Find proteins for P39669 (Rhizobium radiobacter)
Explore P39669 
Go to UniProtKB:  P39669
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download CCD File 
X
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
XL-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.221 
  • R-Value Observed: 0.225 
  • Space Group: I 2 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 85.38α = 90
b = 93.793β = 90
c = 140.293γ = 90
Software Package:
Software NamePurpose
MOSFLMdata reduction
DENZOdata reduction
SCALEPACKdata scaling
PHASERphasing
REFMACrefinement
PDB_EXTRACTdata extraction

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2008-04-22
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2017-10-25
    Changes: Refinement description