title: Oxidative damage in DNA bases revealed by UV resonant Raman spectroscopy.
abstract: We report on the use of the UV Raman technique to monitor the oxidative damage of deoxynucleotide triphosphates (dATP, dGTP, dCTP and dTTP) and DNA (plasmid vector) solutions. Nucleotide and DNA aqueous solutions were exposed to hydrogen peroxide (H2O2) and iron containing carbon nanotubes (CNTs) to produce Fenton's reaction and induce oxidative damage. UV Raman spectroscopy is shown to be maximally efficient to reveal changes in the nitrogenous bases during the oxidative mechanisms occurring on these molecules. The analysis of Raman spectra, supported by numerical computations, revealed that the Fenton's reaction causes an oxidation of the nitrogenous bases in dATP, dGTP and dCTP solutions leading to the production of 2-hydroxyadenine, 8-hydroxyguanine and 5-hydroxycytosine. No thymine change was revealed in the dTTP solution under the same conditions. Compared to single nucleotide solutions, plasmid DNA oxidation has resulted in more radical damage that causes the breaking of the adenine and guanine aromatic rings. Our study demonstrates the advantage of using UV Raman spectroscopy for rapidly monitoring the oxidation changes in DNA aqueous solutions that can be assigned to specific nitrogenous bases.
authors.affiliation: Elettra - Sincrotrone Trieste, Strada Statale 14 km 163.5, Area Science Park, I-34149 Trieste, Italy. francesco.damico@elettra.eu.
authors.forename: Francesco
authors.initials: F
authors.lastname: D'Amico
authors.forename: Francesca
authors.initials: F
authors.lastname: Cammisuli
authors.forename: Riccardo
authors.initials: R
authors.lastname: Addobbati
authors.forename: Clara
authors.initials: C
authors.lastname: Rizzardi
authors.forename: Alessandro
authors.initials: A
authors.lastname: Gessini
authors.forename: Claudio
authors.initials: C
authors.lastname: Masciovecchio
authors.forename: Barbara
authors.initials: B
authors.lastname: Rossi
authors.forename: Lorella
authors.initials: L
authors.lastname: Pascolo
mesh_terms: D004247:DNA / Q000737:chemistry*; D004249:DNA Damage; D006861:Hydrogen Peroxide / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry; D010084:Oxidation-Reduction; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D037742:Nanotubes, Carbon; D004247:DNA; D006861:Hydrogen Peroxide; D007501:Iron