title: Cleavage of stem-and-loop structure DNA by bleomycin. Reaction on the bacteriophage G4 origin of complementary strand synthesis.
abstract: The cleavage by bleomycin-Fe(II) complex in the presence of dithiothreitol of 3'-or 5'-end-labeled DNA from the region of the bacteriophage G4 origin of complementary strand synthesis was investigated by using the DNA-sequencing technique. Bleomycin cleaved a single-stranded DNA substrate preferentially at inverted repeat sequences, which potentially form stem-and-loop structures, while it cleaved double-stranded DNA substrates with different specificity. The results support the formation of three adjoining stem-and-loop structures in the region of the phage G4 origin of complementary strand synthesis under the low-salt conditions used and suggest a difference in the form of the double helix between the stem and the double-stranded DNA fragment. Bleomycin appears to be a useful reagent for searching stem-and-loop structures. The results may also contribute to the understanding of the mode of action of bleomycin as an antitumor antibiotic.
authors.forename: K
authors.initials: K
authors.lastname: Ueda
authors.forename: S
authors.initials: S
authors.lastname: Kobayashi
authors.forename: H
authors.initials: H
authors.lastname: Sakai
authors.forename: T
authors.initials: T
authors.lastname: Komano
mesh_terms: D001435:Bacteriophages / Q000235:genetics*; D001483:Base Sequence; D001761:Bleomycin / Q000494:pharmacology* / Q000031:analogs & derivatives; D004277:DNA, Single-Stranded / Q000378:metabolism; D004279:DNA, Viral / Q000032:analysis*; D004229:Dithiothreitol / Q000494:pharmacology; D009690:Nucleic Acid Conformation / Q000187:drug effects*; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D004277:DNA, Single-Stranded; D004279:DNA, Viral; C023503:iron bleomycin; D001761:Bleomycin; D004229:Dithiothreitol