2DP3

Crystal structure of a double mutant (C202A/A198V) of Triosephosphate isomerase from giardia lamblia


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.181 
  • R-Value Work: 0.175 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Disulfide Bridges in the Mesophilic Triosephosphate Isomerase from Giardia lamblia Are Related to Oligomerization and Activity

Reyes-Vivas, H.Diaz, A.Peon, J.Mendoza-Hernandez, G.Hernandez-Alcantara, G.De la Mora-De la Mora, I.Enriquez-Flores, S.Dominguez-Ramirez, L.Lopez-Velazquez, G.

(2007) J.Mol.Biol. 365: 752-763

  • DOI: 10.1016/j.jmb.2006.10.053
  • Also Cited By: 3PF3

  • PubMed Abstract: 
  • Triosephosphate isomerase from the mesophile Giardia lamblia (GlTIM) is the only known TIM with natural disulfide bridges. We previously found that oxidized and reduced thiol states of GlTIM are involved in the interconversion between native dimers a ...

    Triosephosphate isomerase from the mesophile Giardia lamblia (GlTIM) is the only known TIM with natural disulfide bridges. We previously found that oxidized and reduced thiol states of GlTIM are involved in the interconversion between native dimers and higher oligomeric species, and in the regulation of enzymatic activity. Here, we found that trophozoites and cysts have different oligomeric species of GlTIM and complexes of GlTIM with other proteins. Our data indicate that the internal milieu of G. lamblia is favorable for the formation of disulfide bonds. Enzyme mutants of the three most solvent exposed Cys of GlTIM (C202A, C222A, and C228A) were prepared to ascertain their contribution to oligomerization and activity. The data show that the establishment of a disulfide bridge between two C202 of two dimeric GlTIMs accounts for multimerization. In addition, we found that the establishment of an intramonomeric disulfide bond between C222 and C228 abolishes catalysis. Multimerization and inactivation are both reversed by reducing conditions. The 3D structure of the C202A GlTIM was solved at 2.1 A resolution, showing that the environment of the C202 is prone to hydrophobic interactions. Molecular dynamics of an in silico model of GlTIM when the intramonomeric disulfide bond is formed, showed that S216 is displaced 4.6 A from its original position, causing loss of hydrogen bonds with residues of the active-site loop. This suggests that this change perturb the conformational state that aligns the catalytic center with the substrate, inducing enzyme inactivation.


    Related Citations: 
    • An unusual triosephosphate isomerase from the early divergent eukaryote Giardia lamblia
      Lopez-Velazquez, G.,Molina-Ortiz, D.,Cabrera, N.,Peon-Peralta, J.,Reyes-Vivas, H.
      (2004) Proteins 55: 824


    Organizational Affiliation

    Laboratorio de Bioquimica Genetica, Instituto Nacional de Pediatria, 04530 Mexico, D.F.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Triosephosphate isomerase
A
257Giardia intestinalisMutation(s): 2 
EC: 5.3.1.1
Find proteins for P36186 (Giardia intestinalis)
Go to UniProtKB:  P36186
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.181 
  • R-Value Work: 0.175 
  • Space Group: I 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 55.371α = 90.00
b = 100.443β = 90.00
c = 118.796γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
CNSphasing
CrystalCleardata collection
MOSFLMdata reduction
CrystalCleardata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-01-02
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance