Specific binding of o-phenanthroline at a DNA structural lesion.
DNA intercalators are found to recognize a DNA lesion as a high affinity receptor site. This lesion-specific binding is observed when one strand of a DNA double helix contains an extra, unpaired nucleotide. Our assay for binding controls for the effects of sequence with a series of oligodeoxynucleotide duplexes which are identical except for the location of the lesion, an extra cytidine. Scission of the series of oligodeoxynucleotides by the cuprous complex of ortho-phenanthroline (OP-Cu) indicates that OP-Cu binds at the lesion-specific stable intercalation site, suggesting that OP-Cu intercalates into DNA. The dispersion of OP-Cu scission sites over three residues is consistent with scission via a diffusible intermediate. The location of the scission sites, directly on the 3' side of the lesion, is consistent with minor groove binding in B DNA.
Williams
L D
LD
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115.
Thivierge
J
J
Goldberg
I H
IH
D001483:Base Sequence / Q000187:drug effects; D001665:Binding Sites; D004247:DNA / Q000187:drug effects* / Q000378:metabolism; D004249:DNA Damage; D007364:Intercalating Agents; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation / Q000187:drug effects; D010618:Phenanthrolines / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000032:analysis*
C033365:DNA receptor; D007364:Intercalating Agents; D010618:Phenanthrolines; D011956:Receptors, Cell Surface; D004247:DNA; C025205:1,10-phenanthroline