Molecular interaction between cypermethrin and myoglobin: Spectroscopy and molecular dynamics simulation analysis

Pesticides are essential agricultural chemicals to kill harmful organisms that have been utilized a lot in recent years, but their excessive use has become a great menace to mankind's health. In this study, the effect of cypermethrin (CYP) on myoglobin (Mb) was determined to evaluate the toxicity of insecticides at the protein level using molecular modeling, steady-state fluorescence, ultraviolet-visible (UV-Vis), and FTIR. The Fluorescence spectroscopy displayed that the Mb fluorescence quenched by CYP was the outcome of CYP-Mb composite production. Effective quenching constants (Kq) parameters at three different temperatures were calculated using the modified Stern-Volmer equation to be 1.81 x 10(12), 5.16 x 10(12), and 6.69 x 10(12) M-1S-1, respectively. According to calculations, the enthalpy variation (Delta H degrees) and entropy alteration (Delta S degrees) were 168.11 kJ mol(-1) and 610.51 J.mol(-1)K(-1), respectively, showing that hydrophobic bonds were the main intermolecular power stabilizing the complex. FTIR spectroscopy demonstrated that CYP could alter Mb's global and local conformation, showing its potential toxicity and the structural harm it could inflict. The findings provided important information about the potential toxicity risk of CYP to human health.