Mutagenesis and Metallic DNA

Abstract

Positions of protons in DNA hydrogen bonds are fundamental for the fidelity of the replication process. Because the hydrogen bond is partially covalent the electronic structure of DNA plays an important role in the replication process. Current studies of electron transfer in DNA have shown that simple pictures based on independent electron physics are not sufficient to account for the experimental data. In this paper we propose a model for electron-proton interaction in DNA and its relationship to mutagenesis. We argue that mutations will be more frequent in DNA sequences where electron delocalization occurs. To test our theory we calculate the heat capacity of DNA at low temperatures and compare with the available experimental data in hydrated DNA. We find that our model is in good agreement with the data. We also propose new measurements of infrared absorption which would further test our ideas.