Abstract

We have measured the volatile fingerprints of four pathogenic oral bacteria connected to periodontal disease and dental abscess: Porphyromonas gingivalis (three separate strains), Prevotella intermedia, Prevotella nigrescens and Tannerella forsythia. Volatile fingerprints were measured in vitro from the headspace gas of the bacteria cultured on agar. Concrete identification of new and previously reported bacterial volatiles were performed by a combination of solid phase microextraction (SPME) and offline gas chromatography-mass spectrometry (GC-MS). We also studied the effect of the reduced electric field strength (E/N) on the fragmentation patterns of bacterial volatiles in online proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF-MS). We aimed to discover possible new biomarkers for the studied oral bacteria, as well as to validate the combination of GC-MS and PTR-MS for volatile analysis. Some of the most promising compounds produced include: 1-Methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ), indole, and a cascade of sulphur compounds, such as methanethiol, dimethyl disulphide (DMDS) and dimethyl trisulphide (DMTS). We also found that several compounds, especially alcohols, aldehydes and esters, fragment significantly with the PTR-MS method, when high E/N values are used. We conclude that the studied oral bacteria can be separated by their volatile fingerprints in vitro, which could have importance in clinical and laboratory environments. In addition, using softer ionization conditions can improve the performance of the PTR-MS method in the volatile analysis of certain compounds.
Original languageEnglish
Article number16897
JournalScientific Reports
Volume11
Issue number1
Number of pages12
ISSN2045-2322
DOIs
Publication statusPublished - 19 Aug 2021
MoE publication typeA1 Journal article-refereed

Fields of Science

  • 116 Chemical sciences
  • TRANSFER-REACTION-TIME
  • PTR-TOF-MS
  • FRAGMENTATION PATTERNS
  • ORGANIC-COMPOUNDS
  • IDENTIFICATION
  • SPECIFICITY
  • SENSITIVITY
  • AIR

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