title: Acquired carbapenemases in Enterobactericeae in Singapore, 1996-2012.
abstract: To characterise carbapenemase-producing Enterobacteriaceae (CRE) isolated in Singapore.
  
  
  
  Carbapenemase genes and their flanking regions were amplified and sequenced by PCR. Isolates were typed by pulsed-field gel electrophoresis and multi-locus sequence typing. Plasmids bearing carbapenemase genes were sized by S1 nuclease digestion, Southern blotting, and DNA hybridisation with appropriate probes. Transfer of these plasmids was attempted by conjugation and transformation. Successfully transferred plasmids were characterised by polymerase chain reaction (PCR) replicon typing and restriction digestion.
  
  
  
  Isolates of Klebsiella pneumoniae, Escherichia coli, Enterobacter cloacae and Citrobacter species carried a variety of carbapenemase genes including blaIMP-1, blaIMP-4, blaNDM-1, blaNDM-7, blaOXA-181, blaOXA-48 and blaKPC-2. Apart from K. pneumoniae with blaOXA-181, and some K. pneumoniae with blaNDM-1, the other isolates were not clonal. However there appears to be some spread of plasmids with blaIMP-1, blaNDM-1,blaKPC-2, and blaOXA-48.
  
  
  
  The number of isolates of CRE has increased in Singapore, especially since 2010. There is a diversity of carbapenemase types that reflects the geographical proximity of other countries with CRE.
authors.affiliation: *Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore †Department of Pathology, Singapore General Hospital ‡Duke-NUS Graduate Medical School, Singapore; §School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Tse Hsien
authors.initials: TH
authors.lastname: Koh
authors.forename: Delphine
authors.initials: D
authors.lastname: Cao
authors.forename: Quek Yen
authors.initials: QY
authors.lastname: Shan
authors.forename: Anna
authors.initials: A
authors.lastname: Bacon
authors.forename: Li-Yang
authors.initials: LY
authors.lastname: Hsu
authors.forename: Eng Eong
authors.initials: EE
authors.lastname: Ooi
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D015139:Blotting, Southern; D004352:Drug Resistance, Microbial / Q000502:physiology*; D016521:Electrophoresis, Gel, Pulsed-Field; D004755:Enterobacteriaceae / Q000201:enzymology* / Q000235:genetics; D004756:Enterobacteriaceae Infections / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D058885:Multilocus Sequence Typing; D060885:Multiplex Polymerase Chain Reaction; D012846:Singapore; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D001618:beta-Lactamases; C063912:carbapenemase