5G1O

Aspartate transcarbamoylase domain of human CAD in apo form


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.172 
  • R-Value Work: 0.150 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structure and Functional Characterization of Human Aspartate Transcarbamoylase, the Target of the Anti-Tumoral Drug Pala.

Ruiz-Ramos, A.Velazquez-Campoy, A.Grande-Garcia, A.Moreno-Morcillo, M.Ramon-Maiques, S.

(2016) Structure 24: 1081

  • DOI: 10.1016/j.str.2016.05.001
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • CAD, the multienzymatic protein that initiates and controls de novo synthesis of pyrimidines in animals, associates through its aspartate transcarbamoylase (ATCase) domain into particles of 1.5 MDa. Despite numerous structures of prokaryotic ATCases, ...

    CAD, the multienzymatic protein that initiates and controls de novo synthesis of pyrimidines in animals, associates through its aspartate transcarbamoylase (ATCase) domain into particles of 1.5 MDa. Despite numerous structures of prokaryotic ATCases, we lack structural information on the ATCase domain of CAD. Here, we report the structure and functional characterization of human ATCase, confirming the overall similarity with bacterial homologs. Unexpectedly, human ATCase exhibits cooperativity effects that reduce the affinity for the anti-tumoral drug PALA. Combining structural, mutagenic, and biochemical analysis, we identified key elements for the necessary regulation and transmission of conformational changes leading to cooperativity between subunits. Mutation of one of these elements, R2024, was recently found to cause the first non-lethal CAD deficit. We reproduced this mutation in human ATCase and measured its effect, demonstrating that this arginine is part of a molecular switch that regulates the equilibrium between low- and high-affinity states for the ligands.


    Related Citations: 
    • Expression, Purification, Crystallization and Preliminary X- Ray Diffraction Analysis of the Aspartate Transcarbamoylase Domain of Human Cad.
      Ruiz-Ramos, A.,Lallous, N.,Grande-Garcia, A.,Ramon-Maiques, S.
      (2013) Acta Crystallogr.,Sect.F 69: 1425


    Organizational Affiliation

    Structural Bases of Genome Integrity Group, Structural Biology and Biocomputing Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fdez. Almagro, 3, Madrid 28029, Spain.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CAD PROTEIN
A, B, C, D, E, F
314Homo sapiensMutation(s): 0 
Gene Names: CAD
Find proteins for P27708 (Homo sapiens)
Go to Gene View: CAD
Go to UniProtKB:  P27708
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download SDF File 
Download CCD File 
C, E
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
EDO
Query on EDO

Download SDF File 
Download CCD File 
A, B, E, F
1,2-ETHANEDIOL
ETHYLENE GLYCOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.172 
  • R-Value Work: 0.150 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 82.790α = 90.00
b = 157.890β = 120.00
c = 82.720γ = 90.00
Software Package:
Software NamePurpose
XSCALEdata scaling
PHASERphasing
XDSdata reduction
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2016-06-22
    Type: Initial release
  • Version 1.1: 2016-07-20
    Type: Database references, Structure summary