Mechanisms of Nucleic Acid Oxidation and Cross-linking

University Of Utah, Salt Lake City UT

Investigators

Abstract

The objective of this work is to understand the chemistry involved in the formation of DNA-protein cross links. One electron oxidation of DNA fragments generates radical cations at a number of nucleosides which are then trapped by protein nucleophiles. The protein-DNA adducts will then be characterized by a number of spectroscopic techniques including NMR and LC-ESI-MS/MS. Lastly, a 40 mer DNA sequence, and its complement, will be synthesized. This sequence contains a triple G track, a double G and several AT tracks which compliment GC pairs. This strand will then be prepared using G precursors which have been doped with 10% OG (oxidized G) leading to a random distribution of OG in all 10 G positions in the strand and an average of 1 OG/strand. Reactions of these strands with amine and protein nucleophiles and characterization of the subsequent adducts will be used to identify "hot spot" sequences which are most susceptible to adduct formation following oxidative damage. With this award, the Organic and Macromolecular Chemistry Program is supporting the research of Dr. Cynthia J. Burrows of the Department of Chemistry at the University of Utah. Dr. Burrows will explore the reactions of proteins with DNA fragments which have been damaged by oxidative chemical reactions. Uncovering the chemical reactions involved in oxidative DNA damage is important to a fundamental molecular understanding of the chemical processes involved in aging, cancer and a number of neurological disorders. Students trained as a result of working on this project will gain experience in mechanistic organic chemistry as well as biochemistry, hence they will have skills needed by both the biotechnology and pharmaceutical industries.