Repair of etheno DNA adducts by N-glycosylases.

Abstract

After incubation of chloroacetaldehyde-treated DNA with cell-free homogenates, the excision of N2,3-ethenoguanine and 1,N6-ethenoadenine was observed with a rat brain tumour cell line. The repair mechanism was that of an N-glycosylase. The high specificity of all known DNA N-glycosylases and some unique properties of the enzymatic reaction indicate the existence of N-glycosylases specific for the repair of etheno, or similar, adducts.