Characterization and DNA Stable-Isotope Probing of Methanotrophic Bioaerosols

Kevin P. Dillon, Valdis Krumins, Aishwarya Deshpande, Lee J. Kerkhof, Gediminas Mainelis, Donna E. Fennell

Research output: Contribution to journalArticlepeer-review

2 Scopus citations


The growth and activity of bacteria have been extensively studied in nearly every environment on Earth, but there have been limited studies focusing on the air. Suspended bacteria (outside of water droplets) may stay in the atmosphere for time frames that could allow for growth on volatile compounds, including the potent greenhouse gas methane. We investigated the ability of aerosolized methanotrophic bacteria to grow on methane in the airborne state in rotating gas-phase bioreactors. The physical half-life of the aerial bacterium-sized particles was 3 days. To assess the potential for airborne growth, gas-phase bioreactors containing the aerosolized cultures were amended with 1,500 ppmv 13CH4 or 12CH4. Three of seven experiments demonstrated 13C incorporation into DNA, indicating growth in air. Bacteria associated with the genera Methylocystis and Methylocaldum were detected in 13C-DNA fractions, thus indicating that they were synthesizing new DNA, suggesting growth in air. We conclude that methanotrophs outside of water droplets in the air can potentially grow under certain conditions. Based on our data, humidity seems to be a major limitation to bacterial growth in air. Furthermore, low biomass levels can pose problems for detecting 13C-DNA synthesis in our experimental system.

Original languageEnglish (US)
JournalMicrobiology Spectrum
Issue number6
StatePublished - Nov 2022

All Science Journal Classification (ASJC) codes

  • Physiology
  • Ecology
  • General Immunology and Microbiology
  • Genetics
  • Microbiology (medical)
  • Cell Biology
  • Infectious Diseases


  • aerobiology
  • bacterial growth
  • humidity
  • methane oxidation
  • water availability


Dive into the research topics of 'Characterization and DNA Stable-Isotope Probing of Methanotrophic Bioaerosols'. Together they form a unique fingerprint.

Cite this