1obw
From Proteopedia
| |||||||
, resolution 1.9Å | |||||||
---|---|---|---|---|---|---|---|
Ligands: | |||||||
Activity: | Inorganic diphosphatase, with EC number 3.6.1.1 | ||||||
Coordinates: | save as pdb, mmCIF, xml |
STRUCTURE OF INORGANIC PYROPHOSPHATASE
Overview
Crystalline holo inorganic pyrophosphatase from Escherichia coli was grown in the presence of 250 mM MgCl2. The crystal structure has been solved by Patterson search techniques and refined to an R-factor of 17.6% at 1.9 A resolution. The upper estimate of the root-mean-square error in atomic positions is 0.26 A. These crystals belong to space group P3(2)21 with unit cell dimensions a = b = 110.27 A and c = 78.17 A. The asymmetric unit contains a trimer of subunits, i.e., half of the hexameric molecule. In the central cavity of the enzyme molecule, three Mg2+ ions, each shared by two subunits of the hexamer, are found. In the active sites of two crystallographically independent subunits, two Mg2+ ions are bound. The second active site Mg2+ ion is missing in the third subunit. A mechanism of catalysis is proposed whereby a water molecule activated by a Mg2+ ion and Tyr 55 play essential roles.
About this Structure
1OBW is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of holo inorganic pyrophosphatase from Escherichia coli at 1.9 A resolution. Mechanism of hydrolysis., Harutyunyan EH, Oganessyan VY, Oganessyan NN, Avaeva SM, Nazarova TI, Vorobyeva NN, Kurilova SA, Huber R, Mather T, Biochemistry. 1997 Jun 24;36(25):7754-60. PMID:9201917
Page seeded by OCA on Thu Mar 20 13:08:40 2008