3IG5

Saccharomyces cerevisiae glutamate cysteine ligase in complex with Mg2+ and L-glutamate


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.182 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Mechanistic details of glutathione biosynthesis revealed by crystal structures of Saccharomyces cerevisiae glutamate cysteine ligase.

Biterova, E.I.Barycki, J.J.

(2009) J.Biol.Chem. 284: 32700-32708

  • DOI: 10.1074/jbc.M109.025114
  • Primary Citation of Related Structures:  3IG8

  • PubMed Abstract: 
  • Glutathione is a thiol-disulfide exchange peptide critical for buffering oxidative or chemical stress, and an essential cofactor in several biosynthesis and detoxification pathways. The rate-limiting step in its de novo biosynthesis is catalyzed by g ...

    Glutathione is a thiol-disulfide exchange peptide critical for buffering oxidative or chemical stress, and an essential cofactor in several biosynthesis and detoxification pathways. The rate-limiting step in its de novo biosynthesis is catalyzed by glutamate cysteine ligase, a broadly expressed enzyme for which limited structural information is available in higher eukaryotic species. Structural data are critical to the understanding of clinical glutathione deficiency, as well as rational design of enzyme modulators that could impact human disease progression. Here, we have determined the structures of Saccharomyces cerevisiae glutamate cysteine ligase (ScGCL) in the presence of glutamate and MgCl(2) (2.1 A; R = 18.2%, R(free) = 21.9%), and in complex with glutamate, MgCl(2), and ADP (2.7 A; R = 19.0%, R(free) = 24.2%). Inspection of these structures reveals an unusual binding pocket for the alpha-carboxylate of the glutamate substrate and an ATP-independent Mg(2+) coordination site, clarifying the Mg(2+) dependence of the enzymatic reaction. The ScGCL structures were further used to generate a credible homology model of the catalytic subunit of human glutamate cysteine ligase (hGCLC). Examination of the hGCLC model suggests that post-translational modifications of cysteine residues may be involved in the regulation of enzymatic activity, and elucidates the molecular basis of glutathione deficiency associated with patient hGCLC mutations.


    Organizational Affiliation

    Department of Biochemistry and the Redox Biology Center, University of Nebraska, Lincoln, Nebraska 68588-0664, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Glutamate-cysteine ligase
A
692Saccharomyces cerevisiae (strain ATCC 204508 / S288c)Gene Names: GSH1
EC: 6.3.2.2
Find proteins for P32477 (Saccharomyces cerevisiae (strain ATCC 204508 / S288c))
Go to UniProtKB:  P32477
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MG
Query on MG

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Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
GLU
Query on GLU

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Download CCD File 
A
GLUTAMIC ACID
C5 H9 N O4
WHUUTDBJXJRKMK-VKHMYHEASA-N
 Ligand Interaction
PGE
Query on PGE

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Download CCD File 
A
TRIETHYLENE GLYCOL
C6 H14 O4
ZIBGPFATKBEMQZ-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
CSO
Query on CSO
A
L-PEPTIDE LINKINGC3 H7 N O3 SCYS
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.219 
  • R-Value Work: 0.182 
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 117.444α = 90.00
b = 117.444β = 90.00
c = 165.363γ = 90.00
Software Package:
Software NamePurpose
PHENIXmodel building
HKL-2000data reduction
REFMACrefinement
HKL-2000data scaling
PHENIXphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-09-01
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2012-12-26
    Type: Database references