title: Escherichia coli single-stranded DNA-binding protein alters the structure of intramolecular triplexes in plasmids.
abstract: The ability of the Escherichia coli single-stranded DNA-binding protein (SSB) to recognize structural features associated with intramolecular triplex formation in oligopurine.oligopyrimidine (pur.pyr) inserts in recombinant plasmids was evaluated. The SSB protein binds to supercoiled plasmids and causes a site-preferential increase in OsO4 reactivity of the pyrimidine strand involved in the formation of the Hy-3 isomer of the triplex structure. The E. coli RecA protein showed no reaction with triplexes in similar studies. This behavior is consistent with SSB-mediated unpairing of the H-DNA-forming region.
authors.affiliation: Department of Biochemistry, School of Medicine, University of Alabama at Birmingham 35294.
authors.forename: J
authors.initials: J
authors.lastname: Klysik
authors.forename: M
authors.initials: M
authors.lastname: Shimizu
mesh_terms: D001483:Base Sequence; D004269:DNA, Bacterial / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D004278:DNA, Superhelical / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D009993:Osmium Tetroxide / Q000494:pharmacology; D010957:Plasmids; D011485:Protein Binding
chemical_list: D004269:DNA, Bacterial; D004278:DNA, Superhelical; D004268:DNA-Binding Proteins; D009993:Osmium Tetroxide