Cleavage of stem-and-loop structure DNA by bleomycin. Reaction on the bacteriophage G4 origin of complementary strand synthesis.
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.
Ueda
K
K
Kobayashi
S
S
Sakai
H
H
Komano
T
T
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
D004277:DNA, Single-Stranded; D004279:DNA, Viral; C023503:iron bleomycin; D001761:Bleomycin; D004229:Dithiothreitol