title: Identification of a putative chromosomal replication origin from Helicobacter pylori and its interaction with the initiator protein DnaA.
abstract: The key elements of the initiation of Helicobacter pylori chromosome replication, DnaA protein and putative oriC region, have been characterized. The gene arrangement in the H.pylori dnaA region differs from that found in many other eubacterial dnaA regions (rnpA-rmpH-dnaA-dnaN-recF-gyrB). Helicobacter pylori dnaA is flanked by two open reading frames with unknown function, while dnaN-gyrB and rnpA-rmpH loci are separated from the dnaA gene by 600 and 90 kb, respectively. We show that the dnaA gene encoding initiator protein DnaA is expressed in H.pylori cells. The H.pylori DnaA protein, like other DnaA proteins, can be divided into four domains. Here we demonstrate that the C-terminal domain of H.pylori DnaA protein is responsible for DNA binding. Using in silico and in vitro studies, the putative oriC region containing five DnaA boxes has been located upstream of the dnaA gene. DNase I and gel retardation analyses show that the C-terminal domain of H.pylori DnaA protein specifically binds each of five DnaA boxes.
authors.affiliation: Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigla 12, 53-114 Wroclaw, Poland.
authors.forename: A
authors.initials: A
authors.lastname: Zawilak
authors.forename: S
authors.initials: S
authors.lastname: Cebrat
authors.forename: P
authors.initials: P
authors.lastname: Mackiewicz
authors.forename: A
authors.initials: A
authors.lastname: Król-Hulewicz
authors.forename: D
authors.initials: D
authors.lastname: Jakimowicz
authors.forename: W
authors.initials: W
authors.lastname: Messer
authors.forename: G
authors.initials: G
authors.lastname: Gosciniak
authors.forename: J
authors.initials: J
authors.lastname: Zakrzewska-Czerwinska
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D002876:Chromosomes, Bacterial / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D016480:Helicobacter pylori / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D018741:Replication Origin; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C066312:DnaA protein, Bacteria; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D005982:Glutathione Transferase