DNA Lesions Caused by ROS and RNOS: A Review of Interactions and Reactions Involving Guanine

Recent Advances in the Chemistry of Hydrogen Trioxide (HOOOH)

“…Recently, Shukla and Mishra , reported the results of a theoretical study (B3LYP/aug-cc-pVDZ) of the oxidation of guanine to 8-oxoguanine (8-oxoG, i.e., a strongly mutagenic modification of guanine) with HOOOH in the absence and in presence of a water molecule in the gas phase as in aqueous medium. They found that HOOOH is much more reactive than HOOH in the oxidation of guanine to 8-oxoG.…”

“…The results of this study, together with the biological implications, have been discussed in section 7. 110,111 In an experimental study of the decomposition of hydrogen peroxide (to water and oxygen) in the presence of phosphatidylcholine-containing biomembranes, it was hypothesized that accumulation of HOOH on the vesicle surface increased its local concentration, thus causing the polarization of the O−O bond in the peroxide. 155 oxygen bases as solvents (acetone-d 6 , tetrahydrofuran-d 8 ) is the method of choice for preparation of relatively highly concentrated solutions of HOOOH (up to 0.1 M) without the interfering presence of organic hydrotrioxides (ROOOH).…”

Computational Study of the Formation of C8, C5, and C4 Guanine:Lysine Adducts via Oxidation of Guanine by Sulfate Radical Anion

“…The oxidation of guanine and subsequent reactions of guanine radical have been investigated computationally by a number of groups. − Sevilla and co-workers have studied guanine oxidation and reduction, protonation and deprotonation of guanine radical, and hydroxyl radical addition to guanine. − We have examined the reactions of guanine radical to form 8-oxoG , Sp , Gh , and FAPyG − and the p K a ’s and redox potentials of the intermediates in these pathways. − We have also studied the formation of guanine–thymine cross-links during oxidation by carbonate radical anion and the formation of guanine–lysine cross-links resulting from oxidation mediated by type I and type II photosensitizers. , Dumont and co-workers have investigated DNA–polyamine binding modes and cross-link formation, peroxy radical addition to guanine, and singlet oxygen reactions with guanine. − Liu and co-workers have used electronic structure calculations and guided ion beam mass spectrometry to examine water addition and singlet oxygen addition to guanine and its subsequent reactions. − The formation of 8-aminoguanine and its oxidized and reduced forms have been studied both computationally and experimentally…”

“…Wetmore, Boyd, and co-workers have calculated OH and NO 2 radical addition to nucleobases, as well as ionization potentials and electron affinities of individual nucleobases. − Rothlisberger and co-workers have computed ionization energies and electron affinities of guanine and 8-oxoG in two and three base pair fragments of DNA . Mishra and co-workers have published numerous studies of guanine oxidation by reactive oxygen species. − Nevertheless, computational studies of the formation of guanine–lysine cross-links are rather limited. ,,, …”

Computational Study of the pH-Dependent Competition between Carbonate and Thymine Addition to the Guanine Radical

“…A number of computational studies have addressed the reactions of guanine radical. ,,,− Sevilla and co-workers have investigated guanine oxidation and reduction, protonation and deprotonation of guanine radical, and hydroxyl radical adding to guanine. − We have used DFT calculations to examine the mechanisms for the formation of 8oxoG, Sp, Gh, and FAPyG from guanine radical, , the formation of guanine-lysine cross-links during oxidation mediated by type I and type II photosensitizers, , and the p K a ’s and redox potentials of nucleobases and intermediates in the pathway from guanine radical to Sp and Gh. − Dumont and co-workers have investigated the addition of singlet oxygen to guanine to form 8oxoG and Sp. − Liu and co-workers have used guided ion beam mass spectrometry and density functional calculations to examine gas-phase singlet oxygen reactions with guanine and its oxidation products. − Wetmore, Boyd, and co-workers have calculated ionization potentials and electron affinities of nucleobases, NO 2 radical addition to guanine radical, and hydroxyl radical addition to nucleobases . Mishra and co-workers have published numerous studies of guanine oxidation by reactive oxygen species, − …”