1TU0

Aspartate Transcarbamoylase Catalytic Chain Mutant E50A Complex with Phosphonoacetamide


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.55 Å
  • R-Value Free: 0.279 
  • R-Value Observed: 0.190 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Monitoring the Transition from the T to the R State in E.coli Aspartate Transcarbamoylase by X-ray Crystallography: Crystal Structures of the E50A Mutant Enzyme in Four Distinct Allosteric States.

Stieglitz, K.Stec, B.Baker, D.P.Kantrowitz, E.R.

(2004) J Mol Biol 341: 853-868

  • DOI: 10.1016/j.jmb.2004.06.002
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • A detailed description of the transition that allosteric enzymes undergo constitutes a major challenge in structural biology. We have succeeded in trapping four distinct allosteric states of a mutant enzyme of Escherichia coli aspartate transcarbomyl ...

    A detailed description of the transition that allosteric enzymes undergo constitutes a major challenge in structural biology. We have succeeded in trapping four distinct allosteric states of a mutant enzyme of Escherichia coli aspartate transcarbomylase and determining their structures by X-ray crystallography. The mutant version of aspartate transcarbamoylase in which Glu50 in the catalytic chains was replaced by Ala destabilizes the native R state and shifts the equilibrium towards the T state. This behavior allowed the use of substrate analogs such as phosphonoacetamide and malonate to trap the enzyme in T-like and R-like structures that are distinct from the T-state structure of the wild-type enzyme (as represented by the structure of the enzyme with CTP bound and the R-state structure as represented by the structure with N-(phosphonacetyl)-L-aspartate bound). These structures shed light on the nature and the order of internal structural rearrangements during the transition from the T to the R state. They also suggest an explanation for diminished activity of the E50A enzyme and for the change in reaction mechanism from ordered to random for this mutant enzyme.


    Organizational Affiliation

    Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA 02467, USA.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Aspartate carbamoyltransferase catalytic chain
A, C
310Escherichia coliMutation(s): 1 
Gene Names: pyrBb4245C5345Z5856ECS5222SF4245S4507
EC: 2.1.3.2
Find proteins for P0A786 (Escherichia coli (strain K12))
Go to UniProtKB:  P0A786

Find similar proteins by: Sequence  |  Structure

Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Aspartate carbamoyltransferase regulatory chain
B, D
153Escherichia coliMutation(s): 0 
Gene Names: pyrIb4244C5344Z5855ECS5221
Find proteins for P0A7F3 (Escherichia coli (strain K12))
Go to UniProtKB:  P0A7F3
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PCT
Query on PCT

Download CCD File 
A, C
PHOSPHONOACETAMIDE
C2 H6 N O4 P
AKVIWWJLBFWFLM-UHFFFAOYSA-N
 Ligand Interaction
ZN
Query on ZN

Download CCD File 
B, D
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.55 Å
  • R-Value Free: 0.279 
  • R-Value Observed: 0.190 
  • Space Group: P 3 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 122.2α = 90
b = 122.2β = 90
c = 142.7γ = 120
Software Package:
Software NamePurpose
SHELXmodel building
SHELXL-97refinement
SDMSdata reduction
SDMSdata scaling
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-07-20
    Type: Initial release
  • Version 1.1: 2008-04-30
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Derived calculations, Version format compliance