1QB4: Crystal Structure of Mn(2+)-bound Phosphoenolpyruvate Carboxylase

We have determined the crystal structure of Mn2+-bound Escherichia coli phosphoenolpyruvate carboxylase (PEPC) using X-ray diffraction at 2.6 A resolution, and specified the location of enzyme-bound Mn2+, which is essential for catalytic activity. The electron density map reveals that Mn2+ is bound to the side chain oxygens of Glu-506 and Asp-543, and located at the top of the alpha/beta barrel in PEPC. The coordination sphere of Mn2+ observed in E. coli PEPC is similar to that of Mn2+ found in the pyruvate kinase structure. The model study of Mn2+-bound PEPC complexed with phosphoenolpyruvate (PEP) reveals that the side chains of Arg-396, Arg-581 and Arg-713 could interact with PEP.
PDB ID: 1QB4Download
MMDB ID: 19374
PDB Deposition Date: 1999/4/30
Updated in MMDB: 11/2012 
Experimental Method:
x-ray diffraction
Resolution: 2.6  Å
Source Organism:
Similar Structures:
Biological Unit: tetrameric; determined by author
Molecular Components
Label Count Molecule
Proteins (4 molecules)
Phosphoenolpyruvate Carboxylase
Molecule annotation
Chemicals (8 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB