Study on the Binding of Fluoride, Bromide and Iodide to Ovalbumin by Using Ion-Selective Electrodes
| Autor: | Dejun Chen, Yun-Lai Wang, Gong-Ke Wang, Yan Lu, Changling Yan, Sheng-Hua Gao |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Bromides
Ovalbumin Inorganic chemistry Enthalpy Iodide Calorimetry Buffers Thermodynamic equations Biochemistry Ion selective electrode Fluorides chemistry.chemical_compound Bromide Molecule Molecular Biology chemistry.chemical_classification Binding Sites Temperature Isothermal titration calorimetry General Medicine Hydrogen-Ion Concentration Iodides Kinetics chemistry Regression Analysis Thermodynamics Physical chemistry Ion-Selective Electrodes |
| Zdroj: | The Journal of Biochemistry. 145:309-314 |
| ISSN: | 1756-2651 0021-924X |
| DOI: | 10.1093/jb/mvn170 |
| Popis: | The interactions of F(-), Br(-) and I(-) with ovalbumin (OVA) were studied in acetate buffers of pH 5.68, at 288.15 K, 298.15 K and 308.15 K, using ion-selective electrodes. The data for the ion-protein systems were treated according to the Klotz equation, and the number of binding sites and the binding constants were determined. It is shown that the binding sites of F(-) on OVA molecule are more than those of Br(-) and I(-), and that the binding sites of F(-), Br(-) and I(-) on OVA molecule decreases with increasing temperature. At the same time, our studies indicate that the binding constants for the interactions of F(-), Br(-) and I(-) with OVA show a same trend: They decrease as temperature increases. These were reasonably interpreted with the structural and thermodynamic factors. The thermodynamic functions (DeltaG(), DeltaH(), DeltaS()) at different temperatures were calculated with thermodynamic equations, and the enthalpy change for the interactions were also determined by isothermal titration calorimetry (ITC) at 298.15 K, which indicate that the interactions of F(-), Br(-) and I(-) with OVA are mainly electrostatic interaction. Simultaneously, there are also partial desolvation of solutes and solvent reorganization effect. |
| Databáze: | OpenAIRE |
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