Partial Purification and Characterization of Nuclear Exopolyphosphatase from Saccharomyces cerevisiae Strain with Inactivated PPX1 Gene Encoding a Major Yeast Exopolyphosphatase
| Autor: | Igor S. Kulaev, T. V. Kulakovskaya, L. P. Lichko |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Saccharomyces cerevisiae Proteins
Saccharomyces cerevisiae Biology Biochemistry Substrate Specificity chemistry.chemical_compound Polyphosphates Magnesium Polylysine Exopolyphosphatase Cell Nucleus chemistry.chemical_classification Molecular mass Polyphosphate Cobalt General Medicine biology.organism_classification Molecular biology Yeast Enzyme assay Acid Anhydride Hydrolases Molecular Weight Enzyme chemistry Chromatography Gel biology.protein RNA |
| Zdroj: | Biochemistry (Moscow). 69:270-274 |
| ISSN: | 0006-2979 |
| DOI: | 10.1023/b:biry.0000022056.00041.c3 |
| Popis: | Inactivation of PPX1 encoding the major cytosolic exopolyphosphatase PPX1 in Saccharomyces cerevisiae did not alter exopolyphosphatase activity of the isolated nuclei compared with that in the parent strain. The nuclear exopolyphosphatase of the S. cerevisiae strain deficient in the PPX1 gene was purified 10-fold. According to gel filtration on Superose 6, this enzyme has a molecular mass of approximately 200 kD, and it hydrolyzes polyphosphates with an average chain length of 15 and 208 phosphate residues to the same extent. Its activity is much lower with tripolyphosphate. In the presence of 2.5 mM Mg2+, Km values are 133 and 25 microM in the hydrolysis of polyphosphates with chain lengths of 15 and 208 phosphate residues, respectively. The enzyme activity is stimulated by 2.5 mM Mg2+ and 0.1 mM Co2+ 15- and 31-fold, respectively. RNA does not alter the nuclear exopolyphosphatase activity, while polylysine increases it 2-fold. |
| Databáze: | OpenAIRE |
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