Biological Assembly 1  

 3D View: Structure | Electron Density

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: 141.22 kDa 
• Atom Count: 10550 
• Residue Count: 1153 
• Unique protein chains: 1

2IOB

E. coli Bifunctional glutathionylspermidine synthetase/amidase Apo protein

• DOI: 10.2210/pdb2IOB/pdb

• Classification: LIGASE, HYDROLASE
• Organism(s): Escherichia coli
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2006-10-10 Released: 2006-12-12 
• Deposition Author(s): Pai, C.H., Chiang, B.Y., Ko, T.P., Chou, C.C., Chong, C.M., Yen, F.J., Coward, J.K., Wang, A.H.-J., Lin, C.H.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Free: 0.236 
• R-Value Work: 0.175 

Literature

Dual binding sites for translocation catalysis by Escherichia coli glutathionylspermidine synthetase

Pai, C.H., Chiang, B.Y., Ko, T.P., Chou, C.C., Chong, C.M., Yen, F.J., Chen, S., Coward, J.K., Wang, A.H.-J., Lin, C.H.

(2006) EMBO J 25: 5970-5982

• PubMed: 17124497 
• DOI: 10.1038/sj.emboj.7601440
• Primary Citation of Related Structures:  
  2IO7, 2IO9, 2IO8, 2IOB, 2IOA


• PubMed Abstract: 
  

Most organisms use glutathione to regulate intracellular thiol redox balance and protect against oxidative stress; protozoa, however, utilize trypanothione for this purpose. Trypanothione biosynthesis requires ATP-dependent conjugation of glutathione (GSH) to the two terminal amino groups of spermidine by glutathionylspermidine synthetase (GspS) and trypanothione synthetase (TryS), which are considered as drug targets. GspS catalyzes the penultimate step of the biosynthesis-amide bond formation between spermidine and the glycine carboxylate of GSH. We report herein five crystal structures of Escherichia coli GspS in complex with substrate, product or inhibitor. The C-terminal of GspS belongs to the ATP-grasp superfamily with a similar fold to the human glutathione synthetase. GSH is likely phosphorylated at one of two GSH-binding sites to form an acylphosphate intermediate that then translocates to the other site for subsequent nucleophilic addition of spermidine. We also identify essential amino acids involved in the catalysis. Our results constitute the first structural information on the biochemical features of parasite homologs (including TryS) that underlie their broad specificity for polyamines.

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Organizational Affiliation: 

Institute of Biological Chemistry, Academia Sinica, No. 128 Academia Road Section 2, Nan-Kang, Taipei 11529, Taiwan.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Bifunctional glutathionylspermidine synthetase/amidase	A, B	619	Escherichia coli	Mutation(s): 0  EC: 6.3.1.8 (PDB Primary Data), 3.5.1.78 (PDB Primary Data)
Find proteins for P0AES0 (Escherichia coli (strain K12)) Explore P0AES0  Go to UniProtKB:  P0AES0

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Free: 0.236 
• R-Value Work: 0.175 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 149.267	α = 90
b = 92.964	β = 109.373
c = 108.296	γ = 90

Software Package:

Software Name	Purpose
HKL-2000	data collection
SOLVE	phasing
XTALVIEW	refinement
HKL-2000	data reduction
HKL-2000	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2006-10-10 
• Released Date: 2006-12-12 
Deposition Author(s): Pai, C.H., Chiang, B.Y., Ko, T.P., Chou, C.C., Chong, C.M., Yen, F.J., Coward, J.K., Wang, A.H.-J., Lin, C.H.

Revision History 

• Version 1.0: 2006-12-12
  Type: Initial release
  
• Version 1.1: 2008-05-01
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance