Comparative genome sequence analysis of multidrug-resistant Acinetobacter baumannii

J Bacteriol. 2008 Dec;190(24):8053-64. doi: 10.1128/JB.00834-08. Epub 2008 Oct 17.


The recent emergence of multidrug resistance (MDR) in Acinetobacter baumannii has raised concern in health care settings worldwide. In order to understand the repertoire of resistance determinants and their organization and origins, we compared the genome sequences of three MDR and three drug-susceptible A. baumannii isolates. The entire MDR phenotype can be explained by the acquisition of discrete resistance determinants distributed throughout the genome. A comparison of closely related MDR and drug-susceptible isolates suggests that drug efflux may be a less significant contributor to resistance to certain classes of antibiotics than inactivation enzymes are. A resistance island with a variable composition of resistance determinants interspersed with transposons, integrons, and other mobile genetic elements is a significant but not universal contributor to the MDR phenotype. Four hundred seventy-five genes are shared among all six clinical isolates but absent from the related environmental species Acinetobacter baylyi ADP1. These genes are enriched for transcription factors and transporters and suggest physiological features of A. baumannii that are related to adaptation for growth in association with humans.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Acinetobacter Infections / microbiology
  • Acinetobacter baumannii / classification
  • Acinetobacter baumannii / drug effects
  • Acinetobacter baumannii / genetics*
  • Bacterial Typing Techniques
  • Comparative Genomic Hybridization
  • DNA, Bacterial / genetics
  • Drug Resistance, Multiple, Bacterial / genetics*
  • Genes, Bacterial
  • Genetic Variation
  • Genome, Bacterial*
  • Genomic Islands
  • Humans
  • Molecular Sequence Data
  • Multigene Family
  • Phenotype
  • Sequence Analysis, DNA


  • DNA, Bacterial

Associated data

  • GENBANK/ABXK00000000
  • GENBANK/CP001172
  • GENBANK/CP001182
  • GENBANK/CP001183