Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 51.22 kDa 
• Atom Count: 3864 
• Residue Count: 430 
• Unique protein chains: 1

4HJ2

Crystal Structure Analysis of GSTA1-1 in complex with chlorambucil

• DOI: 10.2210/pdb4HJ2/pdb

• Classification: TRANSFERASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2012-10-12 Released: 2013-03-27 
• Deposition Author(s): Karpusas, M., Chiniadis, L., Labrou, N.E.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free: 0.258 
• R-Value Work: 0.215 

Literature

The interaction of the chemotherapeutic drug chlorambucil with human glutathione transferase A1-1: kinetic and structural analysis.

Karpusas, M., Axarli, I., Chiniadis, L., Papakyriakou, A., Bethanis, K., Scopelitou, K., Clonis, Y.D., Labrou, N.E.

(2013) PLoS One 8: e56337-e56337

• PubMed: 23460799 
• DOI: 10.1371/journal.pone.0056337
• Primary Citation of Related Structures:  
  4HJ2


• PubMed Abstract: 
  

Glutathione transferases (GSTs) are enzymes that contribute to cellular detoxification by catalysing the nucleophilic attack of glutathione (GSH) on the electrophilic centre of a number of xenobiotic compounds, including several chemotherapeutic drugs. In the present work we investigated the interaction of the chemotherapeutic drug chlorambucil (CBL) with human GSTA1-1 (hGSTA1-1) using kinetic analysis, protein crystallography and molecular dynamics. In the presence of GSH, CBL behaves as an efficient substrate for hGSTA1-1. The rate-limiting step of the catalytic reaction between CBL and GSH is viscosity-dependent and kinetic data suggest that product release is rate-limiting. The crystal structure of the hGSTA1-1/CBL-GSH complex was solved at 2.1 Å resolution by molecular replacement. CBL is bound at the H-site attached to the thiol group of GSH, is partially ordered and exposed to the solvent, making specific interactions with the enzyme. Molecular dynamics simulations based on the crystal structure indicated high mobility of the CBL moiety and stabilization of the C-terminal helix due to the presence of the adduct. In the absence of GSH, CBL is shown to be an alkylating irreversible inhibitor for hGSTA1-1. Inactivation of the enzyme by CBL followed a biphasic pseudo-first-order saturation kinetics with approximately 1 mol of CBL per mol of dimeric enzyme being incorporated. Structural analysis suggested that the modifying residue is Cys112 which is located at the entrance of the H-site. The results are indicative of a structural communication between the subunits on the basis of mutually exclusive modification of Cys112, indicating that the two enzyme active sites are presumably coordinated.

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Organizational Affiliation: 

Physics Laboratory, Department of Science, Agricultural University of Athens, Athens, Greece.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Glutathione S-transferase A1	A, B	217	Homo sapiens	Mutation(s): 0  Gene Names: GSTA1 EC: 2.5.1.18 (PDB Primary Data), 1.11.1 (UniProt), 5.3.3 (UniProt)
Find proteins for P08263 (Homo sapiens) Explore P08263  Go to UniProtKB:  P08263
NIH Common Fund Data Resources
PHAROS:  P08263 GTEx:  ENSG00000243955

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
LZ6	A, B	L-gamma-glutamyl-S-(2-{[4-(3-carboxypropyl)phenyl](2-chloroethyl)amino}ethyl)-L-cysteinylglycine C24 H35 Cl N4 O8 S BQVGPQFUMPRIMA-OALUTQOASA-N

External Ligand Annotations
ID	Binding Affinity (Sequence Identity %)
LZ6	Kd :  2950000   nM  PDBBind

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.10 Å
• R-Value Free: 0.258 
• R-Value Work: 0.215 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 99	α = 90
b = 93.53	β = 93.91
c = 51.18	γ = 90

Software Package:

Software Name	Purpose
SCALEPACK	data scaling
CNS	refinement
PDB_EXTRACT	data extraction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2012-10-12 
• Released Date: 2013-03-27 
Deposition Author(s): Karpusas, M., Chiniadis, L., Labrou, N.E.

Revision History 

• Version 1.0: 2013-03-27
  Type: Initial release