The interactions of epoxiconazole and prothioconazole with human serum albumin and bovine serum albumin were investigated using spectroscopic methods complemented with molecular modeling. Spectroscopic techniques showed the formation of pesticide/serum albumin complexes with the static type as the dominant mechanism. The association constants ranged from 3.80 × 104-6.45 × 105 L/mol depending on the pesticide molecule (epoxiconazole, prothioconazole) and albumin type (human or bovine serum albumin). The calculated thermodynamic parameters revealed that the binding of pesticides into serum albumin macromolecules mainly depended on hydrogen bonds and van der Waals interactions. Synchronous fluorescence spectroscopy and the competitive experiments method showed that pesticides bind to subdomain IIA, near tryptophan; in the case of bovine serum albumin also on the macromolecule surface. Concerning prothioconazole, we observed the existence of an additional binding site at the junction of domains I and III of serum albumin macromolecules. These observations were corroborated well by molecular modeling predictions. The conformation changes in secondary structure were characterized by circular dichroism, three-dimensional fluorescence, and UV/VIS absorption methods.

• MeSH
• cirkulární dichroismus metody   MeSH
• epoxidové sloučeniny chemie   MeSH
• fluorescenční spektrometrie metody   MeSH
• hydrofobní a hydrofilní interakce MeSH
• lidé MeSH
• lidský sérový albumin chemie   MeSH
• pesticidy chemie   MeSH
• sekundární struktura proteinů MeSH
• sérový albumin hovězí chemie   MeSH
• simulace molekulového dockingu metody   MeSH
• skot MeSH
• statická elektřina MeSH
• teplota MeSH
• triazoly chemie   MeSH
• vazba proteinů MeSH
• vazebná místa MeSH
• vodíková vazba MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• skot MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Studies of interactions between pesticides and target mammalian proteins are important steps toward understanding the pesticide's toxicity. Using calorimetric and spectroscopic methods, the interaction between triazole fungicide tebuconazole and human serum albumin has been investigated. The spectroscopic techniques showed that fluorescence quenching of human serum albumin by tebuconazole was the result of the formation of tebuconazole/human serum albumin complex with the static type as the dominant mechanism. The association constant was found to be 8.51 × 103 L/mol. The thermodynamic parameters were obtained as ΔH = -56.964 kJ/mol, ΔS = -115.98 J/mol·K. The main active interactions forming the tebuconazole/human serum albumin complex were identified as the interplay between hydrogen bonds and/or van der Waals forces, based on thermodynamic experiments. These binding modes were corroborated well by the predictions of molecular modeling. Hydrogen bonding of tebuconazole with Arg222, Ala215 and Ala291 of human serum albumin played a relevant role in binding. The conformation changes in secondary structure were characterized by circular dichroism and 3D fluorescence spectra.

• MeSH
• diferenciální skenovací kalorimetrie MeSH
• fluorescenční spektrometrie MeSH
• fungicidy průmyslové farmakologie   MeSH
• ibuprofen farmakologie   MeSH
• ketoprofen farmakologie   MeSH
• lidé MeSH
• lidský sérový albumin chemie   metabolismus   MeSH
• simulace molekulového dockingu MeSH
• termodynamika MeSH
• triazoly chemie   farmakologie   MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH