Effect of Netropsin on One-electron Oxidation of DNA

Abstract

One electron oxidation of DNA has been studied extensively over the years. When a charge is injected into a DNA duplex, it migrates through the DNA until it reaches a trap. Upon further reactions, damage occurs in this area and strand cleavage can occur. Many works have been performed to see what can affect this damage to DNA. Netropsin is a minor groove binder that can bind to tracts of four to five A:T base pairs. It has been used in the studies within to determine if it can protect DNA against oxidative damage, caused by one-electron oxidation, when it is bound within the minor groove of the DNA. By using a naphthacenedione derivative as a photosensitizer, several DNA duplexes containing netropsin binding sites as well as those without binding sites, were irradiated at 420 nm, analyzed, and visualized to determine its effect on oxidative damage. It has been determined netropsin creates a quenching sphere of an average of 5.8 * 108 Šwhether bound to the DNA or not. Herein we will show netropsin protects DNA against oxidative damage whether it is free in solutions or bound within the minor groove of a DNA duplex.