Why is the hydrolytic activity of acetylcholinesterase pH dependent? Kinetic study of acetylcholine and acetylthiocholine hydrolysis catalyzed by acetylcholinesterase from electric eel
| Autor: | Karel Komers, Alena Komersová, Alexander Cegan, Václav Lochař, Markéta Kovářová |
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| Rok vydání: | 2018 |
| Předmět: |
Fish Proteins
0301 basic medicine Kinetics Catalysis General Biochemistry Genetics and Molecular Biology 03 medical and health sciences chemistry.chemical_compound Hydrolysis medicine Animals 030102 biochemistry & molecular biology biology Hydrogen-Ion Concentration biology.organism_classification Acetylcholinesterase Acetylcholine Electric eel Enzyme assay 030104 developmental biology Acetylthiocholine chemistry Electrophorus biology.protein medicine.drug Nuclear chemistry |
| Zdroj: | Zeitschrift für Naturforschung C. 73:345-351 |
| ISSN: | 1865-7125 0939-5075 |
| Popis: | The dependence of the activity of acetylcholinesterase from electric eel at a pH value range of 4.8–9.8 (phosphate buffer), regarding acetylcholine and acetylthiocholine hydrolysis, was determined at 25 °C, ionic strength of 0.11 M, and initial substrate concentration of 4 mM. At a pH range of 4.8–9.8, the dependences A(pH) form a sigmoid increasing curve with the maximum catalytic activity at a pH range 8–9.5. For acetylcholine hydrolysis, the kinetic reason for such an increase in A consists mainly of an increase in the rate constant k 2 (Michaelis-Menten) model with increasing pH of the reaction mixture. For acetylthiocholine hydrolysis, the kinetic explication of the determined dependence A(pH) is more complicated. |
| Databáze: | OpenAIRE |
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