Action of spermidine, N¹‐acetylspermidine, and N⁸acetylspermidine at apurinic sites in DNA

Abstract

The cleavage efficiency of spermidine and its acetyl derivatives (Ni-acetylspennidine and Ns-acetylspermidine) at apurinic sites in DNA were examined by PAGE-urea analysis. The three polyamines induced different rates of cleavage when compared at 1 mM concentrations. The order of effectiveness were: spermidine > p-acetylspennidine > Wacetylspermidine. Thus a decrease in efficiency was observed when the first order aminogroups of spermidine were blocked. The N-%mino-group of spermidine was less effective in inducing cleavage at AP-sites than the Ni'-amino-group.Among several proposed models of polyamine-DNA interactions, our results can best be explained by the model postulated by Liquori et al.[6].

The Reductive Conversion of Chromium(VI) by Ascorbate Gives Rise to Apurinic/Apyrimidinic Sites in Isolated DNA

“…In order to reveal AP-sites in isolated DNA, we made use of the fact that certain endonucleases, and polyamines such as putrescine or the tripeptide Lys-Trp-Lys, incise the DNA phosphate backbone at sites where the loss of a base has occurred. This experimental approach has been successfully used to detect AP-sites caused by acid treatment (19)(20)(21), bleomycin and neocarzinostatin (22,23), and X-rays (24). Throughout the present studies we have used AsA at a concentration (1 mM) which is similar to those measured inside cells of a variety of tissues (6,13).…”