Novel DNA-Hybridization Biosensors for Studies of DNA Underwinding Caused by Herbicides and Pesticides

Abstract

Among sensors developed for the detection of environmental pollutants, the biosensors based on DNA recognition abilities play a special role. In this work, a DNA biosensor for the evaluation of DNA damage by toxic agents has been designed which is not based on the DNA biorecognition properties but rather on the sensitivity of the intercalator-probe uptake to the conformational alterations of DNA double-helix. The sensors have been tested to assess DNA alterations caused by an herbicide atrazine. We have found that incubation of the DNA biosensor in atrazine solutions results in the increased capacity of DNA towards binding of an intercalator probe Nile Blue. On the basis of this and other findings, the mechanism of atrazine interactions with DNA double-helix has been elucidated.