title: Study of DNA-deltamethrin binding by voltammetry, competitive fluorescence, thermal denaturation, circular dichroism, and atomic force microscopy techniques.
abstract: The interaction of deltamethrin (DM), a synthetic insecticide, with calf thymus DNA was studied. The cyclic voltammetric (CV) results revealed that DM has two irreversible cathodic peaks. The first peak (a) was devoted to reduction of -CN by 4 electrons and the second peak (b) was devoted to reduction of the -C = C- moiety by two electrons. By using non-linear regression analysis of CV data of peak (a), the binding constant, binding site size, and diffusion coefficient for free DM (D(f)) and DNA-DM (D(b)) were calculated as: 2.6 × 10(4), 1.6, 3.2 × 10(-4)Cm(2) S(-1), and 8.5 × 10(-6)Cm(2) S(-1), respectively. The thermal denaturation, competitive fluorescence, and AFM results revealed that the mode of interaction may be non-intercalative. Also the circular dichroism spectra showed that the conformation of CT DNA was converted from right-handed B-DNA to A-DNA due to the destacking of the adjacent guanine bases in pH 7.3 solution.
authors: Department of Medicinal Chemistry, Faculty of Pharmacy, Kermanshah University of Medical Sciences, Kermanshah, Islamic Republic of Iran. fahmadi@kums.ac.ir
authors: Farhad
authors: F
authors: Ahmadi
authors: Nasibeh
authors: N
authors: Jamali
mesh_terms: D000818:Animals; D001665:Binding Sites; D002417:Cattle; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D059371:DNA, B-Form / Q000737:chemistry / Q000378:metabolism*; D004563:Electrochemistry; D006863:Hydrogen-Ion Concentration; D007306:Insecticides / Q000737:chemistry / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D009570:Nitriles / Q000737:chemistry / Q000378:metabolism*; D011722:Pyrethrins / Q000737:chemistry / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: D059371:DNA, B-Form; D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; C017180:decamethrin; D004247:DNA; C427203:calf thymus DNA