Sequence-Specific Cleavage of Single-Stranded DNA by Oligonucleotides Conjugated to Bleomycin

Abstract

Cleavage of a single-stranded DNA fragment by complementary oligonucleotides conjugated to bleomycin A5 has been investigated. The conjugates efficiently cleave the DNA at the GT sequences near the oligonucleotide binding site. The temperature dependence of the reaction and the composition of the degradation products indicate that the oligonucleotide-linked bleomycin attacks the available double-stranded DNA regions within the oligonucleotide-DNA duplex and in the hairpin DNA region in the vicinity of the carrier oligonucleotide binding site.

Catalytic site-specific cleavage of a DNA-target by an oligonucleotide carrying bleomycin A5

“…As already shown, 12 or 14mer oligonucleotides conjugated to bleomycin and complementary to a single region in DNA fragment (302mer) cleave at the positions near the oligonucleotide binding sites. Degradation of DNA target by free bleomycin or bleomycin conjugated to a noncomplementary oligonucleotide takes place at the same sites which are, however, different from those cleaved by bleomycin coupled with the complementary oligonucleotides (26). These results prove that bleomycin oligonucleotide derivatives can damage DNA-target sites specifically.…”