Journal: J Mol Biol / Year: 2006 Title: Structural basis for detoxification and oxidative stress protection in membranes. Authors: Peter J Holm / Priyaranjan Bhakat / Caroline Jegerschöld / Nobuhiko Gyobu / Kaoru Mitsuoka / Yoshinori Fujiyoshi / Ralf Morgenstern / Hans Hebert / Abstract: Synthesis of mediators of fever, pain and inflammation as well as protection against reactive molecules and oxidative stress is a hallmark of the MAPEG superfamily (membrane associated proteins in ...Synthesis of mediators of fever, pain and inflammation as well as protection against reactive molecules and oxidative stress is a hallmark of the MAPEG superfamily (membrane associated proteins in eicosanoid and glutathione metabolism). The structure of a MAPEG member, rat microsomal glutathione transferase 1, at 3.2 A resolution, solved here in complex with glutathione by electron crystallography, defines the active site location and a cytosolic domain involved in enzyme activation. The glutathione binding site is found to be different from that of the canonical soluble glutathione transferases. The architecture of the homotrimer supports a catalytic mechanism involving subunit interactions and reveals both cytosolic and membraneous substrate entry sites, providing a rationale for the membrane location of the enzyme.
History
Deposition
Jun 7, 2006
Deposition site: RCSB / Processing site: RCSB
Revision 1.0
May 22, 2007
Provider: repository / Type: Initial release
Revision 1.1
May 1, 2008
Group: Version format compliance
Revision 1.2
Jul 13, 2011
Group: Derived calculations / Version format compliance
Method: Crystallographic / Resolution: 3.2 Å / Nominal pixel size: 1.17 Å Magnification calibration: Gold electron diffraction to establish exact unit cell parameters Symmetry type: 2D CRYSTAL
Refinement
Resolution: 3.2→10 Å / Cor.coef. Fo:Fc: 0.619 / Cor.coef. Fo:Fc free: 0.356 / SU B: 29.134 / SU ML: 0.54 / Cross valid method: THROUGHOUT / ESU R: 1.747 / ESU R Free: 0.635 / Stereochemistry target values: MAXIMUM LIKELIHOOD / Details: HYDROGENS HAVE BEEN ADDED IN THE RIDING POSITIONS
Rfactor
Num. reflection
% reflection
Selection details
Rfree
0.37628
457
9.4 %
RANDOM
Rwork
0.33894
-
-
-
obs
0.34237
4409
79.25 %
-
Solvent computation
Ion probe radii: 0.8 Å / Shrinkage radii: 0.8 Å / VDW probe radii: 1.2 Å / Solvent model: MASK