1mjw
STRUCTURE OF INORGANIC PYROPHOSPHATASE MUTANT D42N
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OverviewOverview
The three-dimensional structures of four mutant E. coli inorganic, pyrophosphatases (PPases) with single Asp-->Asn substitutions at positions, 42, 65, 70, and 97 were solved at 1.95, 2.15, 2.10, and 2.20 A resolution, respectively. Asp-42-->Asn and Asp-65-->Asn mutant PPases were prepared as, complexes with sulfate--a structural analog of phosphate, the product of, enzymatic reaction. A comparison of mutant enzymes with native PPases, revealed that a single amino acid substitution changes the position of the, mutated residue as well as the positions of several functional groups and, some parts of a polypeptide chain. These changes are responsible for the, fact that mutant PPases differ from the native ones in their catalytic, properties. The sulfate binding to the mutant PPase active site causes, molecular asymmetry, as shown for the native PPase earlier. The subunit, asymmetry is manifested in different positions of sulfate and several, functional groups, as well as changes in packing of hexamers in crystals, and in cell parameters.
About this StructureAbout this Structure
1MJW is a Single protein structure of sequence from Escherichia coli with SO4 as ligand. Active as Inorganic diphosphatase, with EC number 3.6.1.1 Full crystallographic information is available from OCA.
ReferenceReference
Three-dimensional structures of mutant forms of E. coli inorganic pyrophosphatase with Asp-->Asn single substitution in positions 42, 65, 70, and 97., Avaeva SM, Rodina EV, Vorobyeva NN, Kurilova SA, Nazarova TI, Sklyankina VA, Oganessyan VY, Samygina VR, Harutyunyan EH, Biochemistry (Mosc). 1998 Jun;63(6):671-84. PMID:9668207
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