1MU9

Crystal Structure of a Human Tyrosyl-DNA Phosphodiesterase (Tdp1)-Vanadate Complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.214 
  • R-Value Work: 0.199 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Insights Into Substrate Binding and Catalytic Mechanism of Human Tyrosyl-DNA Phosphodiesterase (Tdp1) from Vanadate- and Tungstate-Inhibited Structures

Davies, D.R.Interthal, H.Champoux, J.J.Hol, W.G.J.

(2002) J.Mol.Biol. 324: 917-932

  • Primary Citation of Related Structures:  1MU7

  • PubMed Abstract: 
  • Tyrosyl-DNA phosphodiesterase (Tdp1) is a DNA repair enzyme that catalyzes the hydrolysis of a phosphodiester bond between a tyrosine residue and a DNA 3'-phosphate. The only known example of such a linkage in eukaryotic cells occurs normally as a tr ...

    Tyrosyl-DNA phosphodiesterase (Tdp1) is a DNA repair enzyme that catalyzes the hydrolysis of a phosphodiester bond between a tyrosine residue and a DNA 3'-phosphate. The only known example of such a linkage in eukaryotic cells occurs normally as a transient link between a type IB topoisomerase and DNA. Thus human Tdp1 is thought to be responsible for repairing lesions that occur when topoisomerase I becomes stalled on the DNA in the cell. Tdp1 has also been shown to remove glycolate from single-stranded DNA containing a 3'-phosphoglycolate, suggesting a role for Tdp1 in repair of free-radical mediated DNA double-strand breaks. We report the three-dimensional structures of human Tdp1 bound to the phosphate transition state analogs vanadate and tungstate. Each structure shows the inhibitor covalently bound to His263, confirming that this residue is the nucleophile in the first step of the catalytic reaction. Vanadate in the Tdp1-vanadate structure has a trigonal bipyramidal geometry that mimics the transition state for hydrolysis of a phosphodiester bond, while Tdp1-tungstate displays unusual octahedral coordination. The presence of low-occupancy tungstate molecules along the narrow groove of the substrate binding cleft is suggestive evidence that this groove binds ssDNA. In both cases, glycerol from the cryoprotectant solution became liganded to the vanadate or tungstate inhibitor molecules in a bidentate 1,2-diol fashion. These structural models allow predictions to be made regarding the specific binding mode of the substrate and the mechanism of catalysis.


    Related Citations: 
    • The Crystal Structure of Human Tyrosyl-DNA Phosphodiesterase, Tdp1
      Davies, D.R.,Interthal, H.,Champoux, J.J.,Hol, W.G.J.
      (2002) Structure 10: 237


    Organizational Affiliation

    Department of Biochemistry and Biological Structure, University of Washington, Box 357742, Seattle, WA 98195-7242, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Tyrosyl-DNA Phosphodiesterase
A, B
485Homo sapiensGene Names: TDP1
EC: 3.1.4.-
Find proteins for Q9NUW8 (Homo sapiens)
Go to Gene View: TDP1
Go to UniProtKB:  Q9NUW8
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download SDF File 
Download CCD File 
A, B
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
VO4
Query on VO4

Download SDF File 
Download CCD File 
A, B
VANADATE ION
O4 V
LSGOVYNHVSXFFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.05 Å
  • R-Value Free: 0.214 
  • R-Value Work: 0.199 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 50.028α = 90.00
b = 104.980β = 90.00
c = 194.297γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
SCALEPACKdata scaling
AMoREphasing
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-01-07
    Type: Initial release
  • Version 1.1: 2008-04-28
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Non-polymer description, Version format compliance