[The influence of adenine, adenosine and adenylic nucleotides on the mutagenic action of hydroxylamine].

The effect of some adenyl precurosors of DNA synthesis on the mutagenic activity oh hydroxylamine (HA) is studied. It is shown that the addition of adenine to a suspension of Escherichia coli Bcells increases the yield of mutants by more than two times as compared with HA alone. The effects of adenosine, AMP and dAMP are somewhat different. It is suggested that the increase of the HAmutagenic effect produced by the addition of adenine may be due to:1) the excess of the amount of adenylic precursors of DNA synthesis over guanilic ones, which promotes the erroneous base-pairing during the replication of the HA modified template; 2) the modification of adenylic precursors by HA into N6-oxy-dATP, and their incorporation into DNA. The mutagenic effect of N6-hydroxyadenosine, the product of the adenine modification by HA, in E. coli Bpur- was studied. The experiments showed that N6-hydroxyadenosine induced about 1% of mutations, a relatively low lethal effect (the cell survival was 80%), and provided a high mutagenic action of this compound.