NUCLEASE MIMETIC EFFECT OF COPPER COMPLEX-COMPOUNDS

The nuclease reaction of a copper complex with the macrocyclic Schiff base ligand tetrabenzo [b, f,j, n] [1, 3, 9, 13] tetraazacyclohexadeci ne (TAAB) at the cleavage of DNA templates has been investigated and c ompared with that of the copper phenanthroline complex. The labeled si ngle-stranded GC containing 25-mer oligonucleotide, single-stranded AT 20-mer oligonucleotide and double-stranded AT 20-mer oligonucleotide with the complemented sequence in the presence of ascorbic acid and ae robic conditions were used as the substrates. The AT specificity of Cu (TAAB)(2+) for both the single-stranded and double-stranded templates may be explained by the specific formation of intercalated complex and oxygen radicals that nick the DNA.