The probing of the interaction between Hb and Malathion in the presence of Fe3+ and Cu2+ by spectroscopic methods

The understanding of noncovalent interactions in protein–ligand complexes is essential in modern biochemistry and should contribute toward the discovery of new drugs. Materials and Methods: The human hemoglobin molecules are a set of very closely related proteins formed by symmetric pairing of a dimer of polypeptide chains, the α- and β-globins, into a tetrameric structural from the lungs to tissues. Malathion is an organophosphate pesticide commonly used on field crops, fruit trees, livestock, agriculture, and for mosquito and medfly control. The interaction between Malathion and human hemoglobin (Hb) in vitro was investigated by means of fluorescence spectroscopy and absorption spectroscopy. Changes in intrinsic fluorescence can be used to monitor structural changes in a protein. The wavelength of absorption and the strength of absorbance of a molecule depend not only on the chemical nature but also on the molecular environment of its chromophores. Results: The fluorescence of Hb was quenched remarkably by Malathion and the quenching mechanism was considered as static quenching by forming a complex. In addition, the results of synchronous fluorescence spectra and three-dimensional fluorescence spectra showed that binding of Malathion with Hb can induce conformational changes in Hb. Conclusions: In this paper, the interaction between Mal and Hb in presence of Fe3+ and Cu2+ were studied that beneficial to design drug against Malathion