Evidence for high-valent iron-oxo species active in the DNA breaks mediated by iron-bleomycin.

The activity of bleomycin is generally attributed to its ability to cleave DNA through the mediation of transition metal salts, molecular oxygen and electrons. Despite the fact that DNA break products are known with great details, the exact nature of the so-called "activated bleomycin", responsible for the activation of C--H bonds of the deoxyriboses, is still a matter of debate. In the present article, we report evidence that high-valent iron-oxo species might be generated by potassium hydrogen persulfate, KHSO5 (a single oxygen atom donor) and are involved in metallobleomycin-mediated DNA breaks.