PMID:9668207

From EcoliWiki
Jump to: navigation, search
Citation

Avaeva, SM, Rodina, EV, Vorobyeva, NN, Kurilova, SA, Nazarova, TI, Sklyankina, VA, Oganessyan, VY, Samygina, VR and Harutyunyan, EH (1998) Three-dimensional structures of mutant forms of E. coli inorganic pyrophosphatase with Asp-->Asn single substitution in positions 42, 65, 70, and 97. Biochemistry Mosc. 63:671-84

Abstract

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.

Links

PubMed

Keywords

Amino Acid Substitution; Asparagine/chemistry; Aspartic Acid/chemistry; Escherichia coli/enzymology; Inorganic Pyrophosphatase; Protein Conformation; Pyrophosphatases/chemistry; X-Ray Diffraction

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

<annotationlinks/>

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.