Introduction: Microorganisms catabolize carbon-containing compounds in their environment during growth, releasing a subset of metabolic byproducts as volatile compounds. However, the relationship between growth media and the production of volatile compounds has been largely unexplored to-date. Objectives: To assess the core and media-specific components of the Klebsiella pneumoniae volatile metabolome via growth in four in vitro culture media. Methods: Headspace volatiles produced by cultures of K. pneumoniae after growth to stationary phase in four rich media (brain heart infusion broth, lysogeny broth, Mueller-Hinton broth, and tryptic soy broth) were analyzed using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC-TOFMS). Differences in the composition of headspace volatiles as a function of growth media were assessed using hierarchical clustering analysis (HCA) and principal component analysis (PCA). Results: A total of 365 volatile compounds were associated with the growth of K. pneumoniae across all media, of which 36 (10%) were common to all growth media, and 148 (41%) were specific to a single medium. In addition, utilizing all K. pneumoniae-associated volatile compounds, strains clustered as a function of growth media, demonstrating the importance of media in determining the metabolic profile of this organism. Conclusion: K. pneumoniae produces a core suite of volatile compounds across all growth media studied, although the volatile metabolic signature of this organism is fundamentally media-dependent.
Bibliographical noteFunding Information:
This work was supported by National Institutes of Health grant R21 AI121076 to JE Hill and Lennart KA Lundblad. Dartmouth College holds an Institutional Program Unifying Population and Laboratory Based Sciences award from the Burroughs Wellcome Fund, and CA Rees was supported by this grant (Grant#1014106). KV Nordick was supported by the Paul K. Richter and Evalyn E. Cook Richter Memorial Fund awarded through Dartmouth College. AE Lewis was supported by the Presidential Scholarship awarded through Dartmouth College. We thank Mavra Nasir and Theodore R Mellors for their aid in editing this manuscript.
© 2017, Springer Science+Business Media New York.
- Comprehensive two-dimensional gas chromatography
- Klebsiella pneumoniae
- Mass spectrometry
- Volatile compounds