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Sonia R W Louro - One of the best experts on this subject based on the ideXlab platform.
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methyl parathion interaction with human and bovine Serum Albumin
Toxicology Letters, 2004Co-Authors: Dilson Silva, Celia Martins Cortez, Jayme Cunhabastos, Sonia R W LouroAbstract:Abstract Methyl parathion (MP; O , O -dimethyl O - p -nitrophenyl phosphorothioate) is an organophosphorous compound still largely used in agriculture and fish hatcheries. This pesticide is not quite selective and is potentially toxic for both vertebrates and invertebrates. Its mechanism of acute toxicity is the inhibition of the enzyme acetylcholinesterase in nervous tissue. Binding of pesticides to plasma proteins is one of many factors that influence their distribution and elimination. The free concentration available for toxic action can be effectively reduced for pesticides with high binding to plasma proteins, although the affinity of pesticides to plasma proteins is often lower than for the enzyme targets. Several different transport proteins exist in blood plasma, but Albumin only is able to bind a wide diversity of xenobiotics reversibly with high affinity. It was already known that parathion (ethyl parathion) exhibits a high affinity to human and bovine Serum Albumins. We studied interactions of methyl parathion with these Albumins by using fluorescence quenching techniques. We selectively excited the fluorescence of tryptophan residues with a 290 nm wavelength light, and observed quenching by titrating human and bovine Serum Albumin solutions with methyl parathion. Stern–Volmer graphs were plotted and quenching constants were estimated. Our results pointed to the formation of complexes of methyl parathion with Albumins. Association constants at 25 °C were 3.07×10 4 (1.2×10 3 ) M −1 for human Serum Albumin, and 1.96×10 4 (±4.5×10 2 ) M −1 for bovine Serum Albumin. At 37 °C, they were 1.08×10 4 (±2.0×10 2 ) M −1 for human Serum Albumin, and 8.16×10 3 (±1.9×10 2 ) M −1 for bovine Serum Albumin. Results also suggest that the primary binding site for methyl parathion on Albumin is close to tryptophan residues 214 of human Serum Albumin and 212 of bovine Serum Albumin.
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Methyl parathion interaction with human and bovine Serum Albumin
Toxicology Letters, 2004Co-Authors: Dilson Silva, Celia Martins Cortez, Jayme Cunha-bastos, Sonia R W LouroAbstract:Methyl parathion (MP; O,O-dimethyl O-p-nitrophenyl phosphorothioate) is an organophosphorous compound still largely used in agriculture and fish hatcheries. This pesticide is not quite selective and is potentially toxic for both vertebrates and invertebrates. Its mechanism of acute toxicity is the inhibition of the enzyme acetylcholinesterase in nervous tissue. Binding of pesticides to plasma proteins is one of many factors that influence their distribution and elimination. The free concentration available for toxic action can be effectively reduced for pesticides with high binding to plasma proteins, although the affinity of pesticides to plasma proteins is often lower than for the enzyme targets. Several different transport proteins exist in blood plasma, but Albumin only is able to bind a wide diversity of xenobiotics reversibly with high affinity. It was already known that parathion (ethyl parathion) exhibits a high affinity to human and bovine Serum Albumins. We studied interactions of methyl parathion with these Albumins by using fluorescence quenching techniques. We selectively excited the fluorescence of tryptophan residues with a 290 nm wavelength light, and observed quenching by titrating human and bovine Serum Albumin solutions with methyl parathion. Stern-Volmer graphs were plotted and quenching constants were estimated. Our results pointed to the formation of complexes of methyl parathion with Albumins. Association constants at 25 degrees C were 3.07 x 10(4) (1.2 x 10(3))M(-1) for human Serum Albumin, and 1.96 x 10(4) (+/- 4.5 x 10(2))M(-1) for bovine Serum Albumin. At 37 degrees C, they were 1.08 x 10(4) (+/- 2.0 x 10(2))M(-1) for human Serum Albumin, and 8.16 x 10(3) (+/- 1.9 x 10(2))M(-1) for bovine Serum Albumin. Results also suggest that the primary binding site for methyl parathion on Albumin is close to tryptophan residues 214 of human Serum Albumin and 212 of bovine Serum Albumin.
Dilson Silva - One of the best experts on this subject based on the ideXlab platform.
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methyl parathion interaction with human and bovine Serum Albumin
Toxicology Letters, 2004Co-Authors: Dilson Silva, Celia Martins Cortez, Jayme Cunhabastos, Sonia R W LouroAbstract:Abstract Methyl parathion (MP; O , O -dimethyl O - p -nitrophenyl phosphorothioate) is an organophosphorous compound still largely used in agriculture and fish hatcheries. This pesticide is not quite selective and is potentially toxic for both vertebrates and invertebrates. Its mechanism of acute toxicity is the inhibition of the enzyme acetylcholinesterase in nervous tissue. Binding of pesticides to plasma proteins is one of many factors that influence their distribution and elimination. The free concentration available for toxic action can be effectively reduced for pesticides with high binding to plasma proteins, although the affinity of pesticides to plasma proteins is often lower than for the enzyme targets. Several different transport proteins exist in blood plasma, but Albumin only is able to bind a wide diversity of xenobiotics reversibly with high affinity. It was already known that parathion (ethyl parathion) exhibits a high affinity to human and bovine Serum Albumins. We studied interactions of methyl parathion with these Albumins by using fluorescence quenching techniques. We selectively excited the fluorescence of tryptophan residues with a 290 nm wavelength light, and observed quenching by titrating human and bovine Serum Albumin solutions with methyl parathion. Stern–Volmer graphs were plotted and quenching constants were estimated. Our results pointed to the formation of complexes of methyl parathion with Albumins. Association constants at 25 °C were 3.07×10 4 (1.2×10 3 ) M −1 for human Serum Albumin, and 1.96×10 4 (±4.5×10 2 ) M −1 for bovine Serum Albumin. At 37 °C, they were 1.08×10 4 (±2.0×10 2 ) M −1 for human Serum Albumin, and 8.16×10 3 (±1.9×10 2 ) M −1 for bovine Serum Albumin. Results also suggest that the primary binding site for methyl parathion on Albumin is close to tryptophan residues 214 of human Serum Albumin and 212 of bovine Serum Albumin.
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Methyl parathion interaction with human and bovine Serum Albumin
Toxicology Letters, 2004Co-Authors: Dilson Silva, Celia Martins Cortez, Jayme Cunha-bastos, Sonia R W LouroAbstract:Methyl parathion (MP; O,O-dimethyl O-p-nitrophenyl phosphorothioate) is an organophosphorous compound still largely used in agriculture and fish hatcheries. This pesticide is not quite selective and is potentially toxic for both vertebrates and invertebrates. Its mechanism of acute toxicity is the inhibition of the enzyme acetylcholinesterase in nervous tissue. Binding of pesticides to plasma proteins is one of many factors that influence their distribution and elimination. The free concentration available for toxic action can be effectively reduced for pesticides with high binding to plasma proteins, although the affinity of pesticides to plasma proteins is often lower than for the enzyme targets. Several different transport proteins exist in blood plasma, but Albumin only is able to bind a wide diversity of xenobiotics reversibly with high affinity. It was already known that parathion (ethyl parathion) exhibits a high affinity to human and bovine Serum Albumins. We studied interactions of methyl parathion with these Albumins by using fluorescence quenching techniques. We selectively excited the fluorescence of tryptophan residues with a 290 nm wavelength light, and observed quenching by titrating human and bovine Serum Albumin solutions with methyl parathion. Stern-Volmer graphs were plotted and quenching constants were estimated. Our results pointed to the formation of complexes of methyl parathion with Albumins. Association constants at 25 degrees C were 3.07 x 10(4) (1.2 x 10(3))M(-1) for human Serum Albumin, and 1.96 x 10(4) (+/- 4.5 x 10(2))M(-1) for bovine Serum Albumin. At 37 degrees C, they were 1.08 x 10(4) (+/- 2.0 x 10(2))M(-1) for human Serum Albumin, and 8.16 x 10(3) (+/- 1.9 x 10(2))M(-1) for bovine Serum Albumin. Results also suggest that the primary binding site for methyl parathion on Albumin is close to tryptophan residues 214 of human Serum Albumin and 212 of bovine Serum Albumin.
Celia Martins Cortez - One of the best experts on this subject based on the ideXlab platform.
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methyl parathion interaction with human and bovine Serum Albumin
Toxicology Letters, 2004Co-Authors: Dilson Silva, Celia Martins Cortez, Jayme Cunhabastos, Sonia R W LouroAbstract:Abstract Methyl parathion (MP; O , O -dimethyl O - p -nitrophenyl phosphorothioate) is an organophosphorous compound still largely used in agriculture and fish hatcheries. This pesticide is not quite selective and is potentially toxic for both vertebrates and invertebrates. Its mechanism of acute toxicity is the inhibition of the enzyme acetylcholinesterase in nervous tissue. Binding of pesticides to plasma proteins is one of many factors that influence their distribution and elimination. The free concentration available for toxic action can be effectively reduced for pesticides with high binding to plasma proteins, although the affinity of pesticides to plasma proteins is often lower than for the enzyme targets. Several different transport proteins exist in blood plasma, but Albumin only is able to bind a wide diversity of xenobiotics reversibly with high affinity. It was already known that parathion (ethyl parathion) exhibits a high affinity to human and bovine Serum Albumins. We studied interactions of methyl parathion with these Albumins by using fluorescence quenching techniques. We selectively excited the fluorescence of tryptophan residues with a 290 nm wavelength light, and observed quenching by titrating human and bovine Serum Albumin solutions with methyl parathion. Stern–Volmer graphs were plotted and quenching constants were estimated. Our results pointed to the formation of complexes of methyl parathion with Albumins. Association constants at 25 °C were 3.07×10 4 (1.2×10 3 ) M −1 for human Serum Albumin, and 1.96×10 4 (±4.5×10 2 ) M −1 for bovine Serum Albumin. At 37 °C, they were 1.08×10 4 (±2.0×10 2 ) M −1 for human Serum Albumin, and 8.16×10 3 (±1.9×10 2 ) M −1 for bovine Serum Albumin. Results also suggest that the primary binding site for methyl parathion on Albumin is close to tryptophan residues 214 of human Serum Albumin and 212 of bovine Serum Albumin.
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Methyl parathion interaction with human and bovine Serum Albumin
Toxicology Letters, 2004Co-Authors: Dilson Silva, Celia Martins Cortez, Jayme Cunha-bastos, Sonia R W LouroAbstract:Methyl parathion (MP; O,O-dimethyl O-p-nitrophenyl phosphorothioate) is an organophosphorous compound still largely used in agriculture and fish hatcheries. This pesticide is not quite selective and is potentially toxic for both vertebrates and invertebrates. Its mechanism of acute toxicity is the inhibition of the enzyme acetylcholinesterase in nervous tissue. Binding of pesticides to plasma proteins is one of many factors that influence their distribution and elimination. The free concentration available for toxic action can be effectively reduced for pesticides with high binding to plasma proteins, although the affinity of pesticides to plasma proteins is often lower than for the enzyme targets. Several different transport proteins exist in blood plasma, but Albumin only is able to bind a wide diversity of xenobiotics reversibly with high affinity. It was already known that parathion (ethyl parathion) exhibits a high affinity to human and bovine Serum Albumins. We studied interactions of methyl parathion with these Albumins by using fluorescence quenching techniques. We selectively excited the fluorescence of tryptophan residues with a 290 nm wavelength light, and observed quenching by titrating human and bovine Serum Albumin solutions with methyl parathion. Stern-Volmer graphs were plotted and quenching constants were estimated. Our results pointed to the formation of complexes of methyl parathion with Albumins. Association constants at 25 degrees C were 3.07 x 10(4) (1.2 x 10(3))M(-1) for human Serum Albumin, and 1.96 x 10(4) (+/- 4.5 x 10(2))M(-1) for bovine Serum Albumin. At 37 degrees C, they were 1.08 x 10(4) (+/- 2.0 x 10(2))M(-1) for human Serum Albumin, and 8.16 x 10(3) (+/- 1.9 x 10(2))M(-1) for bovine Serum Albumin. Results also suggest that the primary binding site for methyl parathion on Albumin is close to tryptophan residues 214 of human Serum Albumin and 212 of bovine Serum Albumin.
Jing Fan - One of the best experts on this subject based on the ideXlab platform.
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interactions between 1 benzoyl 4 p chlorophenyl thiosemicarbazide and Serum Albumin investigation by fluorescence spectroscopy
Bioorganic & Medicinal Chemistry, 2004Co-Authors: Fengling Cui, Jing FanAbstract:The interactions between 1-benzoyl-4-p-chlorphenyl thiosemicarbazide (BCPT) and bovine Serum Albumin (BSA) or human Serum Albumin (HSA) have been studied by fluorescence spectroscopy. By the analysis of fluorescence spectrum and fluorescence intensity, it was showed that BCPT has a strong ability to quench the intrinsic fluorescence of both bovine Serum Albumin and human Serum Albumin through a static quenching procedure. The binding constants of BCPT with BSA or HSA were determined at different temperatures based on the fluorescence quenching results. The binding sites were obtained and the binding force were suggested to be mainly hydrophobic. The effect of common ions on the binding constants was also investigated. A new fluorescence spectroscopy assay of the proteins is presented. The linear range is 5.36–67.0 μg mL−1 with recovery of 101.1% for BSA, and the linear range is 8.28–144.9 μg mL−1 with recovery of 102.6% for HSA. Determination of the proteins in bovine Serum or in human Serum by this method gives results which are very close to those obtained by using Coomassie Brilliant Blue G-250 colorimetry. A practical method was proposed for the determination of BCPT in human Serum samples.
Yukio Kitade - One of the best experts on this subject based on the ideXlab platform.
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Macromolecular interactions of spectinomycin with Bovine Serum Albumin
Journal of Thermal Analysis and Calorimetry, 2013Co-Authors: Mahmoud Kandeel, Mohamed Nabih, Yukio KitadeAbstract:Among the pharmacokinetic parameters of chemotherapeutics, Serum Albumin binding is a critical factor in determining drug distribution and bioavailability. In this study, the binding properties as well as the interaction of spectinomycin with Bovine Serum Albumin was investigated. Spectinomycin showed stronger binding with BSA at higher temperatures, which diminishes by decreasing the temperature. The binding constant of spectinomycin with BSA varied from 3.1 × 10^3 M^−1 at 298 K to 6.3 × 10^3 M^−1 at 313 K. By increasing the temperature, from 298 to 313 K, the binding affinity was increased by twofolds. Thermodynamic analysis indicated changes in Albumin conformation and partial loss of folding during spectinomycin-Albumin binding. The mild-moderate binding affinity of spectinomycin with BSA will be important in determining the drug–drug interactions at the binding sites of BSA. The presence of stronger binding ligand e.g., chloramphenicol, tetracyclines or diclofenac will compete with spectinomycin for its binding sites, therefore, lowering its Serum Albumin binding. The result of this study will be helpful in understanding of the binding properties and mechanisms of interaction of spectinomycin with bovine Serum Albumin.
