Products Derived from the Adenine Moiety

The products derived from A that have been detected in free-radical damaged DNA are depicted in Fig. 12.9. 

A 32P-postlabeling assay has been developed for the cA lesion (Randerath et al. 2001), and interesting data as to their elimination from DNA indicate that this lesion is not repaired base excision repair (BER) as most other damaged 

8-Hydroxyadenine 4,6-Diamino-5-formamido- 5, 8-Cyclo-2 -deoxy-(8-oxo-A) pyrimidine (FAPY-A) adenosine (cA) 

In y-irradiated N20-saturated DNA solution, 0.56 cA lesions per 106 bases are formed per Gy (Dizdaroglu et al. 2001b). This is equivalent to a G value of 0.9 x 10 9 mol J 1. The yield of the cA lesion is hence considerably lower than that of 

N(6)-furfuryladenine (kinetin) is formed in vivo, excreted in the urine, and has been assumed to be a secondary, free-radical-induced DNA product (Bar-ciszewski et al. 1996,1997,1999,2000 Wyszko et al. 2003). 

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