Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | 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: 47.78 kDa 
• Atom Count: 3668 
• Modelled Residue Count: 416 
• Deposited Residue Count: 418 
• Unique protein chains: 1

2GSS

HUMAN GLUTATHIONE S-TRANSFERASE P1-1 IN COMPLEX WITH ETHACRYNIC ACID

• PDB DOI: 10.2210/pdb2GSS/pdb

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


• Deposited: 1996-10-29 Released: 1997-11-12 
• Deposition Author(s): Oakley, A.J., Rossjohn, J., Parker, M.W.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.229 
• R-Value Work: 0.209 
• R-Value Observed: 0.209 

Literature

The three-dimensional structure of the human Pi class glutathione transferase P1-1 in complex with the inhibitor ethacrynic acid and its glutathione conjugate.

Oakley, A.J., Rossjohn, J., Lo Bello, M., Caccuri, A.M., Federici, G., Parker, M.W.

(1997) Biochemistry 36: 576-585

• PubMed: 9012673 
• DOI: 10.1021/bi962316i
• Primary Citation of Related Structures:  
  2GSS, 3GSS


• PubMed Abstract: 
  

The potent diuretic drug ethacrynic acid has been tested in clinical trials as an adjuvant in chemotherapy. Its target is the detoxifying enzyme glutathione transferase which is often found overexpressed in cancer tissues. We have solved the crystal structures of human pi class glutathione transferase P1-1 in complex with the inhibitor ethacrynic acid and its glutathione conjugate. Ethacrynic acid is found to bind in a nonproductive mode to one of the ligand binding sites of the enzyme (the H site) while the glutathione binding site (G site) is occupied by solvent molecules. There are no structural rearrangements of the G site in the absence of ligand. The structure indicates that bound glutathione is required for ethacrynic acid to dock into the H site in a productive binding mode. The binding of the ethacrynic acid-glutathione conjugate shows that the contacts of the glutathione moiety with the protein are identical to those observed in crystal structures of the enzyme with other glutathione-based substrates and inhibitors. The ethacrynic acid moiety of the conjugate binds in the H site in a fashion that has not been observed in crystal structures of other glutathione-based inhibitor complexes. The crystal structures implicate Tyr 108 as an electrophilic participant in the Michael addition of glutathione to ethacrynic acid.

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Related Citations: 

• Three-Dimensional Structure of Class Pi Glutathione S-Transferase from Human Placenta in Complex with S-Hexylglutathione at 2.8 A Resolution
  Reinemer, P., Dirr, H.W., Ladenstein, R., Huber, R., Lo Bello, M., Federici, G., Parker, M.W.
  (1992) J Mol Biol 227: 214

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Organizational Affiliation: 

Ian Porter Foundation Protein Crystallography Laboratory, St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
GLUTATHIONE S-TRANSFERASE P1-1	A, B	209	Homo sapiens	Mutation(s): 0  Gene Names: GSTP1, FAEES3, GST3 EC: 2.5.1.18
UniProt & NIH Common Fund Data Resources
Find proteins for P09211 (Homo sapiens) Explore P09211  Go to UniProtKB:  P09211
PHAROS:  P09211

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
EAA	D [auth A], G [auth B]	ETHACRYNIC ACID C13 H12 Cl2 O4 AVOLMBLBETYQHX-UHFFFAOYSA-N
MES	E [auth A], F [auth A], H [auth B]	2-(N-MORPHOLINO)-ETHANESULFONIC ACID C6 H13 N O4 S SXGZJKUKBWWHRA-UHFFFAOYSA-N
SO4	C [auth A]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Binding Affinity Annotations
ID	Source	Binding Affinity
EAA	PDBBind:  2GSS	Ki: 1.15e+4 (nM) from 1 assay(s)
	Binding MOAD:  2GSS	Ki: 1.15e+4 (nM) from 1 assay(s)
	BindingDB:  2GSS	IC50: min: 3400, max: 2.60e+4 (nM) from 3 assay(s)

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.229 
• R-Value Work: 0.209 
• R-Value Observed: 0.209 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 77.547	α = 90
b = 90.004	β = 97.69
c = 68.883	γ = 90

Software Package:

Software Name	Purpose
AMoRE	phasing
X-PLOR	refinement
DENZO	data reduction
SCALEPACK	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1996-10-29 
• Released Date: 1997-11-12 
Deposition Author(s): Oakley, A.J., Rossjohn, J., Parker, M.W.

Revision History  

• Version 1.0: 1997-11-12
  Type: Initial release
  
• Version 1.1: 2008-03-03
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance