Skip to main content
. Author manuscript; available in PMC: 2017 May 1.
Published in final edited form as: DNA Repair (Amst). 2016 Mar 26;41:42–53. doi: 10.1016/j.dnarep.2016.03.012

Fig. 9. A scheme of how hydrogen peroxide could induce direct double-strand DNA breaks, and how timely repair of one-strand DNA lesions could prevent them.

Fig. 9

DNA duplex is shown in blue, the iron atoms are indicated by colored circles; green circles, Fe(II); orange circles, Fe(III). Red stars, hydroxyl radicals. A, formation of Fe(II)-DNA complex. B, hydrogen peroxide undergoes Fenton's reaction on DNA to generate hydroxyl radical. C, hydroxyl radical breaks one DNA strand. D, repair of the ss-break restores DNA integrity. E, the iron atom is removed from DNA (by Dps). F, in the absence of ss-break repair and subsequent iron removal, another Fenton's reaction with the same iron atom generates another hydroxyl radical nearby. G, the second DNA strand is disrupted opposite the first ss-break, breaking the DNA duplex.