title: DNA conformational analysis in solution by uranyl mediated photocleavage.
abstract: Uranyl mediated photocleavage of double stranded DNA is proposed as a general probing for DNA helix conformation in terms of minor groove width/electronegative potential. Specifically, it is found that A/T-tracts known to constitute strong distamycin binding sites are preferentially photocleaved by uranyl in a way indicating strongest uranyl binding at the center of the minor groove of the AT-region. The A-tracts of kinetoplast DNA show the highest reactivity at the 3'-end of the tract--as opposed to cleavage by EDTA/Fell--in accordance with the minor groove being more narrow at this end. Finally, uranyl photocleavage of the internal control region (ICR) of the 5S-RNA gene yields a cleavage modulation pattern fully compatible with that obtained by DNase I which also--in a more complex way--senses DNA minor groove width.
authors.affiliation: Department of Biochemistry B, Panum Institute, University of Copenhagen, Denmark.
authors.forename: P E
authors.initials: PE
authors.lastname: Nielsen
authors.forename: N E
authors.initials: NE
authors.lastname: Møllegaard
authors.forename: C
authors.initials: C
authors.lastname: Jeppesen
mesh_terms: D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000378:metabolism; D003720:Densitometry; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010777:Photochemistry; D014501:Uranium; D014502:Uranyl Nitrate; D014981:Xenopus
chemical_list: D014502:Uranyl Nitrate; D014501:Uranium; D004247:DNA