Studies on human triosephosphate isomerase
| Autor: | Eugene E. Rozacky, Thomas H. Sawyer, Rodney A. Barton, Robert W. Gracy |
|---|---|
| Rok vydání: | 1971 |
| Předmět: |
chemistry.chemical_classification
Chromatography biology Isoelectric focusing Biophysics Biochemistry Enzyme assay Triosephosphate isomerase chemistry.chemical_compound Isoelectric point Enzyme chemistry Sedimentation equilibrium Glyceraldehyde biology.protein Molecular Biology Dihydroxyacetone phosphate |
| Zdroj: | Archives of Biochemistry and Biophysics. 146:312-320 |
| ISSN: | 0003-9861 |
| DOI: | 10.1016/s0003-9861(71)80069-3 |
| Popis: | A procedure for the isolation of crystalline triosephosphate isomerase from human erythrocytes is described. The isolated enzyme, after a 4500-fold purification has a specific activity of approximately 8000 μmoles of d -glyceraldehyde 3-phosphate converted to dihydroxyacetone phosphate per minute per milligram. The enzyme is judged to be homogeneous by the criteria of analytical ultracentrifugation, zone electrophoresis, and rechromatography. Molecular weight determinations by sedimentation equilibrium ultracentrifugation and gel filtration yield a value of 56,000 daltons. The amino acid composition of the enzyme has also been established. The enzyme from human erythrocytes has been resolved into three catalytically active components by isoelectric focusing. The major peak containing 76% of the triosephosphate isomerase activity has an isoelectric pH of 6.0. The two minor peaks with isoelectric pH values of 5.5 and 6.4 contain 22 and 2% of the enzyme activity, respectively. Several possible explanations for this multiplicity are discussed. |
| Databáze: | OpenAIRE |
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