Studies on the interaction between 3-biotinylate-6-benzimidazole B-nor-cholesterol analogs and ct-DNA

Abstract

The interaction mechanism between 3-biotinylate-6-benzimidazole B-nor-cholesterol analogs and ct-DNA was studied by spectroscopic (ultraviolet spectroscopy (UV), fluorescence spectroscopy, and circular dichroism spectroscopy (CD)), viscosity, and molecular docking technology methods. The UV spectra showed that these compounds induced a color enhancement effect on ct-DNA. The fluorescence spectra verified that the compounds and ct-DNA were bound in the grooves, and the fluorescence quenching process was static quenching. The CD spectra revealed that these compounds did not change the positive peak of the ct-DNA base pair accumulation, while the negative peak of the ct-DNA right-hand helix exhibited a slight hyperchromic effect. The viscosity test indicated that the reaction between these compounds and ct-DNA did not significantly change the viscosity. According to the molecular docking results, the three compounds mainly interacted with the ct-DNA via the groove mode, and all of them expressed a weak electrostatic effect, which was slightly stronger for compound 3.