Mechanism of DNA Cleavage Induced by Fe2+ Autoxidation

Bulletin of the Korean chemical society

Jong Moon Kim¹  Seog K. Kim¹ 

关键词: Iron autoxidation;    Fenton reaction;    Reactive oxygen species;    Hydroxyl radical;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

This work investigated the difference between Fe2+ autoxidation-induced and Fenton-type cleavage of pBR322 plasmid DNA. •OH generation reactions in the absence and presence of H2O2 under various conditions were also investigated. Although both the Fe2+ autoxidation and Fenton-type reactions showed DNA cleavage and •OH generation, there were significant differences in their efficiencies and reaction rates. The rate and efficiency of the cleavage reaction were higher in the absence of 1.0 mM of H2O2 than in its presence in 20 mM phosphate buffer. In contrast, the •OH generation reaction was more prominent in the presence of H2O2 and showed a pH-independent, fast initial reaction rate, but the rate was decreased in the absence of H2O2 at across the entire tested pH range. Studies using radical scavengers on DNA cleavage and •OH generation reactions in both the absence and presence of H2O2 confirmed that both reactions spontaneously involved the active oxygen species •OH, O2 •−, 1O2 and H2O2, indicating that a similar process may participate in both reactions. Based on the above observations, a new mechanism for the Fe2+ autoxidation-induced DNA cleavage reaction is proposed.

【 授权许可】

Unknown