Effect of Incubation Temperature on Antibiotic Resistance and Virulence Factors of Acinetobacter baumannii ATCC 17978

Antimicrob Agents Chemother. 2017 Dec 21;62(1):e01514-17. doi: 10.1128/AAC.01514-17. Print 2018 Jan.

Abstract

Acinetobacter baumannii is a notorious opportunistic pathogen that is prevalent mainly in hospital settings. The ability of A. baumannii to adapt and to survive in a range of environments has been a key factor for its persistence and success as an opportunistic pathogen. In this study, we investigated the effect of temperature on the clinically relevant phenotypes displayed by A. baumannii at 37°C and 28°C. Surface-associated motility was significantly reduced at 28°C, while biofilm formation on plastic surfaces was increased at 28°C. Decreased susceptibility to aztreonam and increased susceptibility to trimethoprim-sulfamethoxazole were observed at 28°C. No differences in virulence, as assayed in a Galleria mellonella model, were observed. Proteomic analysis showed differential expression of 629 proteins, of which 366 were upregulated and 263 were downregulated at 28°C. Upregulation of the Csu and iron uptake proteins at 28°C was a key finding for understanding some of the phenotypes displayed by A. baumannii at 28°C.

Keywords: biofilm; phenyl acetate; thermoregulation; twitching motility.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acinetobacter baumannii / drug effects*
  • Acinetobacter baumannii / pathogenicity
  • Acinetobacter baumannii / physiology*
  • Adaptation, Physiological / physiology*
  • Animals
  • Anti-Bacterial Agents / pharmacology*
  • Aztreonam / pharmacology*
  • Biofilms / growth & development
  • Gene Expression Regulation, Bacterial
  • Microbial Sensitivity Tests
  • Moths / microbiology
  • Temperature*
  • Trimethoprim, Sulfamethoxazole Drug Combination / pharmacology*
  • Virulence Factors

Substances

  • Anti-Bacterial Agents
  • Virulence Factors
  • Trimethoprim, Sulfamethoxazole Drug Combination
  • Aztreonam