Base Excision Repair Processing of X-Ray-Induced Free Radical DNA Damage

摘要

About 60-70% of the cellular DNA damage produced by ionising radiation is caused by hydroxyl radicals that are formed by the radiolysis of water. These include single-strand breaks, sites of base loss, and a plethora of modified purines and pyrimidines (for a review see 2). Many of these damages are stable and thus have the potential to produce biological consequences. The spectrum of radiation-induced free radical damage overlaps that of damage produced during normal oxidative metabolism, and because of this, the repair system that removes free radical DNA damage, base excision repair (BER), is highly conserved between prokaryotes and eukaryotes.