title: Expanding the Klebsiella pneumoniae volatile metabolome using advanced analytical instrumentation for the detection of novel metabolites.
abstract: OBJECTIVE
  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).
  
  
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Geisel School of Medicine at Dartmouth, Hanover, NH, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Rees
authors.affiliation: Thayer School of Engineering at Dartmouth, Hanover, NH, USA.
authors.forename: F A
authors.initials: FA
authors.lastname: Franchina
authors.affiliation: Dartmouth College, Hanover, NH, USA.
authors.forename: K V
authors.initials: KV
authors.lastname: Nordick
authors.affiliation: Dartmouth College, Hanover, NH, USA.
authors.forename: P J
authors.initials: PJ
authors.lastname: Kim
authors.affiliation: Geisel School of Medicine at Dartmouth, Hanover, NH, USA.|Thayer School of Engineering at Dartmouth, Hanover, NH, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Hill
mesh_terms: D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D007711:Klebsiella pneumoniae / Q000254:growth & development / Q000378:metabolism*; D055442:Metabolome; D055432:Metabolomics; D052617:Solid Phase Microextraction; D055549:Volatile Organic Compounds / Q000032:analysis / Q000737:chemistry
chemical_list: D055549:Volatile Organic Compounds
keywords: 
  Klebsiella pneumoniae
  ; comprehensive two-dimensional gas chromatography; headspace analysis; mass spectrometry; metabolomics; volatile molecules