Expanding the Klebsiella pneumoniae volatile metabolome using advanced analytical instrumentation for the detection of novel metabolites

J Appl Microbiol. 2017 Mar;122(3):785-795. doi: 10.1111/jam.13372. Epub 2017 Feb 1.

Abstract

Aims: The purpose of this study was to identify the volatile molecules produced by the pathogenic Gram-negative bacterium Klebsiella pneumoniae (ATCC 13883) during in vitro growth using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOFMS).

Methods and results: Klebsiella pneumoniae ATCC 13883 was incubated in lysogeny broth to mid-exponential and stationary growth phases. Headspace volatile molecules from culture supernatants were concentrated using solid-phase microextraction (SPME) and analysed via GC×GC-TOFMS. Ninety-two K. pneumoniae-associated volatile molecules were detected, of which 78 (85%) were detected at both phases of growth and 14 (15%) were detected at either mid-exponential or stationary growth phases.

Conclusions: This study has increased the total number of reported K. pneumoniae-associated volatile molecules from 77 to 150, demonstrating the sensitivity and resolution achieved by employing GC×GC-TOFMS for the analysis of bacterial headspace volatiles.

Significance and impact of the study: This study represents an early-stage comprehensive volatile metabolomic analysis of an opportunistic bacterial pathogen. Characterizing the volatile molecules produced by K. pneumoniae during in vitro growth could provide us with a better understanding of this organisms' metabolism, an area that has not been extensively studied to date.

Keywords: Klebsiella pneumoniae; comprehensive two-dimensional gas chromatography; headspace analysis; mass spectrometry; metabolomics; volatile molecules.

MeSH terms

  • Gas Chromatography-Mass Spectrometry / methods
  • Klebsiella pneumoniae / growth & development
  • Klebsiella pneumoniae / metabolism*
  • Metabolome*
  • Metabolomics
  • Solid Phase Microextraction
  • Volatile Organic Compounds / analysis
  • Volatile Organic Compounds / chemistry

Substances

  • Volatile Organic Compounds