title: Cloning, analysis, and expression of the gene for inorganic pyrophosphatase of Aquifex pyrophilus and properties of the enzyme.
abstract: The gene encoding Aquifex pyrophilus (Apy) pyrophosphatase was cloned and sequenced. The deduced amino acid sequence of Apy pyrophosphatase showed a 94.2% homology to Aquifex aeolicus (Aae) pyrophosphatase. The gene exhibits a difference in the codon usage at the third position from Aae pyrophosphatase. The gene was expressed under the control of a tac promoter in E. coli. The recombinant Apy pyrophosphatase was purified 18.7-fold with a 52.8% yield and a specific activity of 26.2 U mg(-1) protein. The native enzyme has a homotetramer of 177 amino acids. The enzyme shows optimal activity in pH 7.5. The optimum temperature was approximately 70 degrees C. A divalent cation was absolutely required for the enzyme activity; Mg2+ was the most effective.
authors.affiliation: Department of Genetic Engineering, Sungkyunkwan University, Suwon, Korea.
authors.forename: Hyang-Sook
authors.initials: HS
authors.lastname: Hoe
authors.forename: Hyun-Kyu
authors.initials: HK
authors.lastname: Kim
authors.forename: Suk-Tae
authors.initials: ST
authors.lastname: Kwon
mesh_terms: D000595:Amino Acid Sequence; D001419:Bacteria / Q000201:enzymology* / Q000235:genetics; D001483:Base Sequence; D003001:Cloning, Molecular; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011755:Pyrophosphatases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013696:Temperature
chemical_list: D011755:Pyrophosphatases