1LII

STRUCTURE OF T. GONDII ADENOSINE KINASE BOUND TO ADENOSINE 2 AND AMP-PCP


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.73 Å
  • R-Value Free: 0.225 
  • R-Value Work: 0.189 
  • R-Value Observed: 0.189 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal structures of Toxoplasma gondii adenosine kinase reveal a novel catalytic mechanism and prodrug binding.

Schumacher, M.A.Scott, D.M.Mathews, I.I.Ealick, S.E.Roos, D.S.Ullman, B.Brennan, R.G.

(2000) J Mol Biol 298: 875-893

  • DOI: 10.1006/jmbi.2000.3753
  • Primary Citation of Related Structures:  
    1LIK, 1LIJ, 1LII, 1LIO

  • PubMed Abstract: 
  • Adenosine kinase (AK) is a key purine metabolic enzyme from the opportunistic parasitic protozoan Toxoplasma gondii and belongs to the family of carbohydrate kinases that includes ribokinase. To understand the catalytic mechanism of AK, we determined the structures of the T ...

    Adenosine kinase (AK) is a key purine metabolic enzyme from the opportunistic parasitic protozoan Toxoplasma gondii and belongs to the family of carbohydrate kinases that includes ribokinase. To understand the catalytic mechanism of AK, we determined the structures of the T. gondii apo AK, AK:adenosine complex and the AK:adenosine:AMP-PCP complex to 2.55 A, 2.50 A and 1.71 A resolution, respectively. These structures reveal a novel catalytic mechanism that involves an adenosine-induced domain rotation of 30 degrees and a newly described anion hole (DTXGAGD), requiring a helix-to-coil conformational change that is induced by ATP binding. Nucleotide binding also evokes a coil-to-helix transition that completes the formation of the ATP binding pocket. A conserved dipeptide, Gly68-Gly69, which is located at the bottom of the adenosine-binding site, functions as the switch for domain rotation. The synergistic structural changes that occur upon substrate binding sequester the adenosine and the ATP gamma phosphate from solvent and optimally position the substrates for catalysis. Finally, the 1.84 A resolution structure of an AK:7-iodotubercidin:AMP-PCP complex reveals the basis for the higher affinity binding of this prodrug over adenosine and thus provides a scaffold for the design of new inhibitors and subversive substrates that target the T. gondii AK.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Vollum Institute, Oregon Health Sciences University, Portland 97201-3098, USA.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
adenosine kinaseA363Toxoplasma gondiiMutation(s): 0 
Gene Names: AK
EC: 2.7.1.20
UniProt
Find proteins for Q9TVW2 (Toxoplasma gondii)
Explore Q9TVW2 
Go to UniProtKB:  Q9TVW2
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ACP
Query on ACP

Download Ideal Coordinates CCD File 
E [auth A]PHOSPHOMETHYLPHOSPHONIC ACID ADENYLATE ESTER
C11 H18 N5 O12 P3
UFZTZBNSLXELAL-IOSLPCCCSA-N
 Ligand Interaction
ADN
Query on ADN

Download Ideal Coordinates CCD File 
D [auth A]ADENOSINE
C10 H13 N5 O4
OIRDTQYFTABQOQ-KQYNXXCUSA-N
 Ligand Interaction
CL
Query on CL

Download Ideal Coordinates CCD File 
C [auth A]CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
MG
Query on MG

Download Ideal Coordinates CCD File 
B [auth A]MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
ADNKi:  8900   nM  BindingDB
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.73 Å
  • R-Value Free: 0.225 
  • R-Value Work: 0.189 
  • R-Value Observed: 0.189 
  • Space Group: P 21 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 167.8α = 90
b = 47.1β = 90
c = 44.45γ = 90
Software Package:
Software NamePurpose
EPMRphasing
TNTrefinement
MOSFLMdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2002-05-15
    Type: Initial release
  • Version 1.1: 2008-04-28
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance