Biodegradation of trace atmospheric gases and the feasibility of microbial aerobiotechnology

Synopsis

Methane is a potent greenhouse gas with an 84 times greater warming potential than carbon dioxide over a 20-year timeframe. It is responsible for about 30% of the warming that has occurred since pre-industrial times. Rapidly reducing methane emissions is a key objective of diverse governments and organizations to minimize climate impacts in the near term. The only known biological sink for methane is methanotrophic bacteria, which convert methane to carbon dioxide and biomass. These bacteria live in diverse environments including soil and freshwater, where they are responsible for preventing the emission of an estimated 625 Tg of methane per year. Although the abundance and physiology of methanotrophs has been well characterized in terrestrial and aquatic environments, they have not been well characterized in a newly described ecosystem, the aeromicrobiome. The aeromicrobiome, comprised of airborne microbes present mainly in the troposphere, is poorly understood. Indeed, microbes in the aeromicrobiome face numerous challenges, and their metabolic activity has not been well characterized. This talk will discuss these challenges, and present approaches that are being used by the Fowler lab to assess the distribution and metabolic activity of microbes, with a focus on methanotrophs, in the aeromicrobiome. Biotechnologies based on airborne microorganisms could potentially make important contributions to mitigating greenhouse gas emissions in certain environments.