title: Opening of the replication origin of Escherichia coli by DnaA protein with protein HU or IHF.
abstract: Opening of the three tandem repeats of a 13-mer in the replication origin (oriC) of Escherichia coli is a prime event in the replication in vitro of minichromosomes (Bramhill, D., and Kornberg, A. (1988) Cell 54, 915-918). DnaA, the initiator protein, requires protein HU or IHF, along with a millimolar level of ATP and negative superhelical density in the plasmid to open this region. The extent of opening, as judged by cleavage by a single-strand-specific endonuclease (i.e. P1 nuclease), correlated closely with replication of the oriC plasmid. In an initial complex, preceding opening of the 13-mers, the footprint of DnaA protein bound by ATP covered its four 9-mer recognition sequences. The footprint of the nucleotide-free form of the protein, by contrast, was more extensive and thus, less specific.
authors.affiliation: Department of Biochemistry, Stanford University School of Medicine, California 94305-5307.
authors.forename: D S
authors.initials: DS
authors.lastname: Hwang
authors.forename: A
authors.initials: A
authors.lastname: Kornberg
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D001483:Base Sequence; D004261:DNA Replication; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D005798:Genes, Bacterial; D034982:Integration Host Factors; D007700:Kinetics; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D010957:Plasmids; D011485:Protein Binding; D015183:Restriction Mapping
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; C066312:DnaA protein, Bacteria; D034982:Integration Host Factors; D009838:Oligodeoxyribonucleotides; C040330:histone-like protein HU, bacteria