3CSJ

Human glutathione s-transferase p1-1 in complex with chlorambucil


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.176 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

The anti-cancer drug chlorambucil as a substrate for the human polymorphic enzyme glutathione transferase P1-1: kinetic properties and crystallographic characterisation of allelic variants.

Parker, L.J.Ciccone, S.Italiano, L.C.Primavera, A.Oakley, A.J.Morton, C.J.Hancock, N.C.Bello, M.L.Parker, M.W.

(2008) J.Mol.Biol. 380: 131-144

  • DOI: 10.1016/j.jmb.2008.04.066
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The commonly used anti-cancer drug chlorambucil is the primary treatment for patients with chronic lymphocytic leukaemia. Chlorambucil has been shown to be detoxified by human glutathione transferase Pi (GST P1-1), an enzyme that is often found over- ...

    The commonly used anti-cancer drug chlorambucil is the primary treatment for patients with chronic lymphocytic leukaemia. Chlorambucil has been shown to be detoxified by human glutathione transferase Pi (GST P1-1), an enzyme that is often found over-expressed in cancer tissues. The allelic variants of GST P1-1 are associated with differing susceptibilities to leukaemia and differ markedly in their efficiency in catalysing glutathione (GSH) conjugation reactions. Here, we perform detailed kinetic studies of the allelic variants with the aid of three representative co-substrates. We show that the differing catalytic properties of the variants are highly substrate-dependent. We show also that all variants exhibit the same temperature stability in the range 10 degrees C to 45 degrees C. We have determined the crystal structures of GST P1-1 in complex with chlorambucil and its GSH conjugate for two of these allelic variants that have different residues at positions 104 and 113. Chlorambucil is found to bind in a non-productive mode to the substrate-binding site (H-site) in the absence of GSH. This result suggests that under certain stress conditions where GSH levels are low, GST P1-1 can inactivate the drug by sequestering it from the surrounding medium. However, in the presence of GSH, chlorambucil binds in the H-site in a productive mode and undergoes a conjugation reaction with GSH present in the crystal. The crystal structure of the GSH-chlorambucil complex bound to the *C variant is identical with the *A variant ruling out the hypothesis that primary structure differences between the variants cause structural changes at the active site. Finally, we show that chlorambucil is a very poor inhibitor of the enzyme in contrast to ethacrynic acid, which binds to the enzyme in a similar fashion but can act as both substrate and inhibitor.


    Organizational Affiliation

    Biota Structural Biology Laboratory, St. Vincent's Institute of Medical Research, Fitzroy, Victoria 3065, Australia.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Glutathione S-transferase P
A, B
209Homo sapiensMutation(s): 0 
Gene Names: GSTP1 (FAEES3, GST3)
EC: 2.5.1.18
Find proteins for P09211 (Homo sapiens)
Go to Gene View: GSTP1
Go to UniProtKB:  P09211
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

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

Download SDF File 
Download CCD File 
B
CHLORAMBUCIL
C14 H19 Cl2 N O2
JCKYGMPEJWAADB-UHFFFAOYSA-N
 Ligand Interaction
MES
Query on MES

Download SDF File 
Download CCD File 
A, B
2-(N-MORPHOLINO)-ETHANESULFONIC ACID
C6 H13 N O4 S
SXGZJKUKBWWHRA-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.176 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 77.840α = 90.00
b = 89.930β = 97.70
c = 69.070γ = 90.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
X-PLORphasing
PDB_EXTRACTdata extraction
DENZOdata reduction
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2008-04-09 
  • Released Date: 2008-07-01 
  • Deposition Author(s): Parker, L.J.
  • This entry supersedes: 21GS

Revision History 

  • Version 1.0: 2008-07-01
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance