[Ultrasonic cleavage of DNA in complexes with Ag(I), Cu(II), Hg(II)]

We investigated a phenomenon of ultrasonic cleavage of DNA complexed with transition metal cations Ag(I), Cu(II) and Hg(II). We found the statistically significant dependence of relative intensity of cleavage on cation type and concentration. Each cation may cause two different types of distortion in the DNA double-helix depending on whether it binds to major or minor DNA groove. The intensity of ultrasonic cleavage decreases if cation binds to the major DNA groove; the intensity of cleavage increases if cation binds to the minor DNA groove and disturbs the hydrogen bonds of complementary base pairs or it intercalates between bases. Both types of DNA distortion can affect the intensity of N-S interconversion of deoxyribose.