[Fundamental model assays on chemical damages to ribonucleic acids caused by oxygen radicals in aqueous solution]

A partial decomposition of RNA molecules in Saccharomyces cerevisiae is caused by photochemically produced superoxide anion radical (O2-.). Hydroxyl radicals (OH.) lead to complete destruction of RNA. Such radicals as originating from peroxidase-hydrogen peroxide reaction cause a partial decomposition of RNA molecules. All RNA species are damaged to the same extent by radicals. Damages due to oxygen radicals can be prevented or reduced by strong radical captors (dimethyl sulfoxide, 1,4-diazabicyclo-(2,2,2)-octane or superoxide dismutase). All these reactions proceed in aqueous solution. Correlations with the use of radicals in radiotherapy are discussed.