title: Identification of oligonucleotide fragments produced in a strand scission reaction of the d(C-G-C-G-C-G) duplex by bleomycin.
abstract: To elucidate the mechanism of DNA strand scission by bleomycin, a d(C-G-C-G-C-G) duplex was treated with the bleomycin-iron ion complex in the presence of H2O2 and degradation products (1, 2, cytosine and deoxyguanosine 5'-phosphate) were identified. 1 and 2 contain a carboxymethyl group attached to the 3'-terminal phosphoryl group of d(C-Gp) and d(C-G-C-Gp), respectively. These compounds were identified by UV, 1H and 31P NMR spectroscopy and paper electrophoresis. 1 was synthesized from the protected dinucleotide and glycolic acid and the proton NMR spectrum was identical to that of 1 obtained as a degradation product. Thus the oligonucleotide fragments produced by the action of bleomycin on DNA were directly identified and cleavage of the C3'-C4' bond of the sugar residues was proved.
mesh_terms: D001761:Bleomycin / Q000031:analogs & derivatives; D055598:Chemical Phenomena; D002621:Chemistry; D004247:DNA; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D009838:Oligodeoxyribonucleotides; D009841:Oligonucleotides
chemical_list: D009838:Oligodeoxyribonucleotides; D009841:Oligonucleotides; C023503:iron bleomycin; D001761:Bleomycin; D004247:DNA