Repine J E, Pfenninger O W, Talmage D W, Berger E M, Pettijohn D E
Proc Natl Acad Sci U S A. 1981 Feb;78(2):1001-3. doi: 10.1073/pnas.78.2.1001.
Eighty percent of the single-strand DNA breaks induced by gamma-irradiation were prevented by the hydroxyl radical (.OH) scavenger dimethyl sulfoxide (Me2SO); CH4 was generated in the process as a product of the interaction of .OH and Me2SO. In contrast, Me2SO completely blocked DNA nicking by an iron/H2O2 system which produces .OH but smaller amounts of CH4 from Me2SO. Because Me2SO prevented DNA breaks from the more efficient iron/H2O2 system but only blocked 80% of irradiation-mediated nicking, the results suggest that .OH is responsible for 80% of the DNA single-strand breaks and the remaining 20% is due to interactions not involving .OH.
γ射线照射诱导产生的单链DNA断裂，有80%可被羟基自由基（·OH）清除剂二甲基亚砜（Me2SO）抑制；在此过程中会生成CH4，它是·OH与Me2SO相互作用的产物。相比之下，Me2SO完全抑制了铁/过氧化氢体系导致的DNA切口，该体系会产生·OH，但与Me2SO反应生成的CH4量较少。由于Me2SO能抑制更高效的铁/过氧化氢体系导致的DNA断裂，但只能阻断80%的辐射介导切口，结果表明，·OH导致了80%的DNA单链断裂，其余20%是由不涉及·OH的相互作用所致。
