Title
Deciphering the mechanism of interaction of edifenphos with calf thymus DNA
Author
Ajaz Ahmad, Masood Ahmad
Year
2018
Journal
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
Abstract
Edifenphos is an important organophosphate pesticide with many antifungal and anti-insecticidal properties but it may cause potential hazards to human health. In this work, we have tried to explore the binding mode of action and mechanism of edifenphos to calf thymus DNA (CT-DNA). Several experiments such as ultraviolet-visible absorption spectra and emission spectroscopy showed complex formation between edifenphos and CT-DNA and low binding constant values supporting groove binding mode. These results were further confirmed by circular dichroism (CD), CT-DNA melting studies, viscosity measurements, density functional theory and molecular docking. CD study suggests that edifenphos does not alter native structure of CT-DNA. Isothermal calorimetry reveals that binding of edifenphos with CT-DNA is enthalpy driven process. Competitive binding assay and effect of ionic strength showed that edifenphos binds to CT-DNA via groove binding manner. Hence, edifenphos is a minor groove binder preferably interacting with A-T regions with docking score − 6.84 kJ/mol.
Instrument
J-815
Keywords
Circular dichroism, DNA structure, DNA binding, Thermal stability, Thermodynamics, Biochemistry