Complete genome sequence of Acinetobacter baumannii MDR-TJ and insights into its mechanism of antibiotic resistance

J Antimicrob Chemother. 2012 Dec;67(12):2825-32. doi: 10.1093/jac/dks327. Epub 2012 Sep 5.


Objectives: To determine the genome sequence of Acinetobacter baumannii strain MDR-TJ and characterize the mechanisms of multidrug resistance in this strain.

Methods: The whole-genome sequence was determined using Roche 454 GS FLX Titanium. Subsequently, the gaps were closed by sequencing PCR products. The genome of strain MDR-TJ was annotated using IMG ER, the RAST annotation server and the BASys bacterial annotation system. The comM gene of MDR-TJ was examined to identify a possible antibiotic resistance island. Based on the results of multilocus sequence typing, we investigated seven multidrug-resistant A. baumannii strains belonging to global clone 2 (GC2) isolated from Asia, Australia and Europe to determine the backbone shared by resistance islands of GC2 isolates.

Results: The A. baumannii strain MDR-TJ genome consists of a circular chromosome and a plasmid, pABTJ1. Strain MDR-TJ was assigned to sequence type ST2. Strain MDR-TJ harbours a 41.6 kb resistance island designated RI(MDR-TJ), which can be derived from the backbone of Tn6167 through the insertion of a Tn6022 into the 3'-end of the tetA(B) gene. Comparative analysis showed that transposon Tn6022 and its truncated forms prevailed in the antibiotic resistance islands of GC2 isolates. The carbapenem resistance gene bla(OXA-23) carried by transposon Tn2009 is located on a putatively conjugative plasmid, pABTJ1.

Conclusions: A. baumannii strain MDR-TJ belongs to GC2 and is resistant to multiple antibiotics. A. baumannii MDR-TJ harbours a genomic resistance island that interrupts the comM gene. The carbapenem resistance of MDR-TJ is mediated by a putatively conjugative plasmid, pABTJ1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acinetobacter Infections / microbiology
  • Acinetobacter baumannii / classification
  • Acinetobacter baumannii / drug effects
  • Acinetobacter baumannii / genetics*
  • Acinetobacter baumannii / isolation & purification
  • Anti-Bacterial Agents / pharmacology
  • Asia
  • Australia
  • DNA, Bacterial / chemistry*
  • DNA, Bacterial / genetics*
  • Drug Resistance, Bacterial*
  • Europe
  • Genes, Bacterial
  • Genome, Bacterial*
  • Genomic Islands
  • Genotype
  • Humans
  • Molecular Sequence Data
  • Multilocus Sequence Typing
  • Plasmids
  • Sequence Analysis, DNA*


  • Anti-Bacterial Agents
  • DNA, Bacterial

Associated data

  • GENBANK/CP004359
  • RefSeq/NC_017847
  • RefSeq/NC_017848