2UUI

Crystal structure of Human Leukotriene C4 Synthase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.237 
  • R-Value Work: 0.196 
  • R-Value Observed: 0.198 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Structural Basis for Synthesis of Inflammatory Mediators by Human Leukotriene C4 Synthase.

Martinez Molina, D.Wetterholm, A.Kohl, A.Mccarthy, A.A.Niegowski, D.Ohlson, E.Hammarberg, T.Eshaghi, S.Haeggstrom, J.Z.Nordlund, P.

(2007) Nature 448: 613

  • DOI: 10.1038/nature06009
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Cysteinyl leukotrienes are key mediators in inflammation and have an important role in acute and chronic inflammatory diseases of the cardiovascular and respiratory systems, in particular bronchial asthma. In the biosynthesis of cysteinyl leukotriene ...

    Cysteinyl leukotrienes are key mediators in inflammation and have an important role in acute and chronic inflammatory diseases of the cardiovascular and respiratory systems, in particular bronchial asthma. In the biosynthesis of cysteinyl leukotrienes, conversion of arachidonic acid forms the unstable epoxide leukotriene A4 (LTA4). This intermediate is conjugated with glutathione (GSH) to produce leukotriene C4 (LTC4) in a reaction catalysed by LTC4 synthase: this reaction is the key step in cysteinyl leukotriene formation. Here we present the crystal structure of the human LTC4 synthase in its apo and GSH-complexed forms to 2.00 and 2.15 A resolution, respectively. The structure reveals a homotrimer, where each monomer is composed of four transmembrane segments. The structure of the enzyme in complex with substrate reveals that the active site enforces a horseshoe-shaped conformation on GSH, and effectively positions the thiol group for activation by a nearby arginine at the membrane-enzyme interface. In addition, the structure provides a model for how the omega-end of the lipophilic co-substrate is pinned at one end of a hydrophobic cleft, providing a molecular 'ruler' to align the reactive epoxide at the thiol of glutathione. This provides new structural insights into the mechanism of LTC4 formation, and also suggests that the observed binding and activation of GSH might be common for a family of homologous proteins important for inflammatory and detoxification responses.


    Organizational Affiliation

    Division of Biophysics, Karolinska Institutet, 17177 Stockholm, Sweden.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
LEUKOTRIENE C4 SYNTHASE
A
156Homo sapiensMutation(s): 0 
Gene Names: LTC4S
EC: 4.4.1.20 (PDB Primary Data), 2.5.1 (UniProt)
Membrane protein
Mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Membrane-Associated Proteins in Eicosanoid and Glutathione Metabolism (MAPEG)
Protein: 
Leukotriene LTC4 Synthase in complex with glutathione
Find proteins for Q16873 (Homo sapiens)
Go to UniProtKB:  Q16873
NIH Common Fund Data Resources
PHAROS  Q16873
Protein Feature View
  • Reference Sequence
Small Molecules
Ligands 4 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
LMT
Query on LMT

Download CCD File 
A
DODECYL-BETA-D-MALTOSIDE
C24 H46 O11
NLEBIOOXCVAHBD-QKMCSOCLSA-N
 Ligand Interaction
PLM
Query on PLM

Download CCD File 
A
PALMITIC ACID
C16 H32 O2
IPCSVZSSVZVIGE-UHFFFAOYSA-N
 Ligand Interaction
SO4
Query on SO4

Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
NI
Query on NI

Download CCD File 
A
NICKEL (II) ION
Ni
VEQPNABPJHWNSG-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.237 
  • R-Value Work: 0.196 
  • R-Value Observed: 0.198 
  • Space Group: F 2 3
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 169.67α = 90
b = 169.67β = 90
c = 169.67γ = 90
Software Package:
Software NamePurpose
REFMACrefinement

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-07-17
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance