Purification and Characterization of 6-Pyruvoyl Tetrahydropterin Synthase from Human Pituitary Gland
Autor: | Otmar D. Wiestler, Claus W. Heizmann, U. Redweik, Jaime Guzman, Peter Hunziker, Nenad Blau, Gabriele Schoedon |
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Rok vydání: | 1992 |
Předmět: |
Tris
Pituitary gland Macromolecular Substances Biochemistry chemistry.chemical_compound Pituitary Gland Posterior Pituitary Gland Anterior Salmon medicine Animals Humans Amino Acids chemistry.chemical_classification ATP synthase biology Molecular mass Chemistry Antibodies Monoclonal Substrate (chemistry) Tetrahydrobiopterin Chromatography Ion Exchange Biopterin Immunohistochemistry Rats Molecular Weight Alcohol Oxidoreductases Kinetics medicine.anatomical_structure Enzyme Isoelectric point Liver Pituitary Gland Chromatography Gel biology.protein Drosophila Electrophoresis Polyacrylamide Gel Isoelectric Focusing Phosphorus-Oxygen Lyases medicine.drug |
Zdroj: | Europe PubMed Central |
ISSN: | 2504-2564 0013-9432 |
DOI: | 10.1159/000468806 |
Popis: | 6-Pyruvoyl tetrahydropterin synthase, the enzyme that catalyses the conversion of 7,8-dihydroneopterin triphosphate to 6-pyruvoyl tetrahydropterin, was purified 3,330-fold from human pituitary gland with an overall recovery of 30%. The native enzyme has a molecular mass of 68 kD and consists of four identical subunits of 16.5 kD. The pH optimum of the enzyme in Tris/HCl buffer is 7.5. The enzyme is dependent on Mg2+ and NADPH and has a Michaelis-Menten constant of 10 microM for its natural substrate, 7,8-dihydroneopterin triphosphate. The isoelectric point of the human enzyme is 4.3-4.6. The human pituitary gland enzyme is heat instable in contrast to the enzymes from human, rat and salmon liver, and Drosophila head. The amino acid composition showed remarkably high content of acidic amino acids Asp and Glu. The N-terminus was found to be blocked. |
Databáze: | OpenAIRE |
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