title: Sequence analysis of pKF3-70 in Klebsiella pneumoniae: probable origin from R100-like plasmid of Escherichia coli.
abstract: BACKGROUND
  Klebsiella pneumoniae is a clinically significant species of bacterium which causes a variety of diseases. Clinical treatment of this bacterial infection is greatly hindered by the emergence of multidrug-resistant strains. The resistance is largely due to the acquisition of plasmids carrying drug-resistant as well as pathogenic genes, and its conjugal transfer facilitates the spread of resistant phenotypes.
  
  
  RESULTS
  The 70,057 bp plasmid pKF3-70, commonly found in Klebsiella pneumoniae, is composed of five main functional modules, including regions involved in replication, partition, conjugation, transfer leading, and variable regions. This plasmid is more similar to several Escherichia coli plasmids than any previously reported K. pneumoniae plasmids and pKF3-70 like plasmids share a common and conserved backbone sequence. The replication system of the pKF3-70 is 100% identical to that of RepFII plasmid R100 from E. coli. A beta-lactamase gene ctx-m-14 with its surrounding insertion elements (ISEcp1, truncated IS903 and a 20 bp inverted repeat sequence) may compose an active transposon which is directly bordered by two putative target repeats "ATTAC."
  
  
  CONCLUSIONS
  The K. pneumoniae plasmid pKF3-70 carries an extended-spectrum beta-lactamase gene, ctx-m-14. The conjugative characteristic makes it a widespread plasmid among genetically relevant genera which poses significant threat to public health.
authors.affiliation: Institute of Biomedical Informatics/Zhejiang Provincial Key Laboratory of Medical Genetics, Wenzhou Medical College, Wenzhou, China.
authors.forename: Huiguang
authors.initials: H
authors.lastname: Yi
authors.forename: Yali
authors.initials: Y
authors.lastname: Xi
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: Junrong
authors.initials: J
authors.lastname: Wang
authors.forename: Jinyu
authors.initials: J
authors.lastname: Wu
authors.forename: Teng
authors.initials: T
authors.lastname: Xu
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Biaobang
authors.initials: B
authors.lastname: Chen
authors.forename: Meili
authors.initials: M
authors.lastname: Lin
authors.forename: Huan
authors.initials: H
authors.lastname: Wang
authors.forename: Mingming
authors.initials: M
authors.lastname: Zhou
authors.forename: Jinsong
authors.initials: J
authors.lastname: Li
authors.forename: Zuyuan
authors.initials: Z
authors.lastname: Xu
authors.forename: Shouguang
authors.initials: S
authors.lastname: Jin
authors.forename: Qiyu
authors.initials: Q
authors.lastname: Bao
mesh_terms: D001483:Base Sequence; D003227:Conjugation, Genetic; D004926:Escherichia coli / Q000235:genetics*; D007711:Klebsiella pneumoniae / Q000235:genetics*; D008969:Molecular Sequence Data; D010957:Plasmids; D012689:Sequence Homology, Nucleic Acid