title: Characterization of pKU701, a 2.5-kb plasmid, in a Japanese Helicobacter pylori isolate.
abstract: A cryptic plasmid of Helicobacter pylori, pKU701 (accession number AB078638), was isolated and the complete nucleotide sequence was determined. No drug resistance properties were mediated by pKU701. The 2454b pKU701 sequence, which had a 38% content of G-C residues, generated one polypeptide from a single open reading frame (ORF1). Extensive sequence homology was evident between pKU701 and ORF1 of H. pylori plasmid pHPO100 (repA, 88.8% identity) as well as ORF3 of plasmid pHPS1 (repB, 80.2% identity), but pKU701 showed only 46.3% homology with ORF1 of plasmid pHPK255 (repA). Tandem direct repeats of a 33-bp segment were found in pKU701 outside ORF1, but there were no inverted repeat ends such as those found in typical insertion sequences. The ability of drug resistance plasmids to replicate in H. pylori is probably limited, so chromosomal mutation may be a more likely cause of resistance.
authors.affiliation: Department of Microbiology, Kitasato University School of Medicine, 1-15-1 Kitasato, Sagamihara-shi, Kanagawa 228-8555, Japan.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Hosaka
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Okamoto
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Irinoda
authors.forename: Satoru
authors.initials: S
authors.lastname: Kaieda
authors.forename: Wasaburo
authors.initials: W
authors.lastname: Koizumi
authors.forename: Katunori
authors.initials: K
authors.lastname: Saigenji
authors.forename: Matsuhisa
authors.initials: M
authors.lastname: Inoue
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000737:chemistry; D001483:Base Sequence; D020090:Chromosome Segregation; D003001:Cloning, Molecular; D004261:DNA Replication; D024901:Drug Resistance, Multiple, Bacterial; D016480:Helicobacter pylori / Q000187:drug effects / Q000235:genetics*; D006801:Humans; D007564:Japan; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins