English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

The oxidation products obtained from the reaction of peroxynitrite (ONOO-) with dG include-among others-8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), 2,2-diamino-4[(2-deoxy-beta-d-erythro-pentafuranosyl)amino]-5(2H)-oxazolone (oxazolone), spiroiminodihydantoin, and N1-(beta-d-erythro-pentofuranosyl)-5-guanidinohydantoin (guanidinohydantoin). In the present work, the formation of these products from the treatment of calf thymus DNA with varying amounts of ONOO- was studied quantitatively in vitro. 13C-, 15N-labeled standards were synthesized for the nucleosides of interest, and calf thymus DNA was reacted with ONOO- and digested enzymatically down to the nucleoside level. Specific modifications in the DNA were measured by HPLC separation followed by electrospray ionization tandem mass spectrometric analysis in the selected reaction-monitoring mode. Artifacts of the above four oxidation products, arising from oxidation of dG and/or 8-oxodG during DNA digestion and subsequent workup, were evaluated with 7-15N-dG and/or stable-isotope-labeled 8-oxodG as internal standards. Levels of artifactual 8-oxodG were about 5/10(6) nucleosides. The artifacts of spiroiminodihydantoin and guanidinohydantoin, arising from 8-oxodG, were 3.7% and 0.6% of the measured 8-oxodG values, respectively. No artifacts of oxazolone were detected. 8-OxodG and oxazolone were formed dose-dependently in DNA treated with ONOO-, while the levels of spiroiminodihydantoin and guanidinohydantoin increased significantly at low ONOO- doses, and then dropped off at higher ONOO- doses. The complexity of these dose-response relationships is likely due to the dual role of peroxynitrite as both an oxidant and a nucleophile in competition with water.

Quantitation of Four Guanine Oxidation Products from Reaction of DNA with Varying Doses of Peroxynitrite