Heavy metal-nucleotide interactions. 15. Reactions of calf thymus DNA with the electrophiles methylmercury(II) nitrate, cis-dichlorodiammineplatinum(II), and trans-dichlorodiammineplatinum(II) studied using Raman difference spectroscopy. Evidence for the formation of C-DNA upon metalation.

This study details the reactions of the electrophiles CH3Hg(NO3), cis-[PtCl2(NH3)2] (cis-DDP) and trans-[PtCl2(NH3)2] (trans-DDP) with calf thymus DNA using Raman and Raman difference spectroscopy. The order of CH2Hg(II) binding to calf thymus DNA is G greater than or equal to T greater than C greater than A. The electrophilic attack of cis- and trans-DDP on calf thymus DNA produces different orders of binding cis-DDP-G greater than C approximately A much greater than T, trans-DDP-G approximately C approximately A much greater than T. The reaction of CH3Hg(II) with DNA results in a decrease in the percentage of B-form DNA, whereas the reactions of cis-and trans-DDP with DNA decrease the percentage of B-DNA and cause the formation of C-DNA structure.