1D2A

CRYSTAL STRUCTURE OF A YEAST LOW MOLECULAR WEIGHT PROTEIN TYROSINE PHOSPHATASE (LTP1) COMPLEXED WITH THE ACTIVATOR ADENINE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.243 
  • R-Value Work: 0.182 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural and mechanistic basis for the activation of a low-molecular weight protein tyrosine phosphatase by adenine.

Wang, S.Stauffacher, C.V.Van Etten, R.L.

(2000) Biochemistry 39: 1234-1242


  • PubMed Abstract: 
  • Although the activation of low-molecular weight protein tyrosine phosphatases by certain purines and purine derivatives was first described three decades ago, the mechanism of this rate enhancement was unknown. As an example, adenine activates the ye ...

    Although the activation of low-molecular weight protein tyrosine phosphatases by certain purines and purine derivatives was first described three decades ago, the mechanism of this rate enhancement was unknown. As an example, adenine activates the yeast low-molecular weight protein tyrosine phosphatase LTP1 more than 30-fold. To examine the structural and mechanistic basis of this phenomenon, we have determined the crystal structure of yeast LTP1 complexed with adenine. In the crystal structure, an adenine molecule is found bound in the active site cavity, sandwiched between the side chains of two large hydrophobic residues at the active site. Hydrogen bonding to the side chains of other active site residues, as well as some water-mediated hydrogen bonds, also helps to fix the position of the bound adenine molecule. An ordered water was found in proximity to the bound phosphate ion present in the active site, held by hydrogen bonding to N3 of adenine and Odelta1 of Asp-132. On the basis of the crystal structure, we propose that this water molecule is the nucleophile that participates in the dephosphorylation of the phosphoenzyme intermediate. Solvent isotope effect studies show that there is no rate-determining transfer of a solvent-derived proton in the transition state for the dephosphorylation of the phosphoenzyme intermediate. Such an absence of general base catalysis of water attack is consistent with the stability of the leaving group, namely, the thiolate anion of Cys-13. Consequently, adenine activates the enzyme by binding and orienting a water nucleophile in proximity to the phosphoryl group of the phosphoenzyme intermediate, thus increasing the rate of the dephosphorylation step, a step that is normally the rate-limiting step of this enzymatic reaction.


    Related Citations: 
    • Cloning and Characterization of a Saccharomyces cerevisiae Gene Encoding the Low Molecular Weight Protein-tyrosine Phosphatase
      Ostanin, K.,Pokalsky, C.,Wang, S.,Van Etten, R.L.
      (1995) J.Biol.Chem. 270: 18491
    • Crystal Structure of a Low Molecular Weight Protein Tyrosine Phosphatase from Saccharomyces cerevisiae and its Complex with the Substrate p-Nitrophenyl Phosphate
      Wang, S.,Tabernero, L.,Zhang, M.,Harms, E.,Van Etten, R.L.,Stauffacher, C.V.
      () TO BE PUBLISHED --: --


    Organizational Affiliation

    Departments of Chemistry and Biological Sciences, Purdue University, West Lafayette, IN 47907, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
TYROSINE PHOSPHATASE
A, B
160Saccharomyces cerevisiae (strain ATCC 204508 / S288c)Gene Names: LTP1
EC: 3.1.3.48, 3.1.3.2
Find proteins for P40347 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Go to UniProtKB:  P40347
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
A, B
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
CL
Query on CL

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Download CCD File 
A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
ADE
Query on ADE

Download SDF File 
Download CCD File 
B
ADENINE
C5 H5 N5
GFFGJBXGBJISGV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.243 
  • R-Value Work: 0.182 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 51.492α = 90.00
b = 63.272β = 90.00
c = 97.590γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
X-PLORrefinement
DENZOdata reduction
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-03-01
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance