Abstract
In the era of global warming, solutions to reduce greenhouse gases (GHG) emissions are urgently needed. Nitrous oxide (N2O) has a global warming potential almost 300 times higher than CO2, and accounts for 8% of anthropogenic GHG emissions. The majority of N2O results from microbial activity in managed and engineered ecosystems. Over the last decade, extensive research efforts focused on biological N2O formation and on strategies to prevent it. However, no general approach could be established to date due to the challenge of simultaneously controlling multiple biological processes in dynamic environments. In this project, I propose to shift the paradigm, from controlling microbial N2O production to harnessing biological N2O consumption. To this end, I will focus on denitrification, the only known microbial pathway capable to reduce N2O to innocuous N2. As such, denitrification holds promise to play a pivotal role in global efforts to control N2O emissions. For the first time, I will use parallel, continuously operated bioreactors (chemostats) to enrich denitrifying communities under highly controlled and fully comparable conditions. This novel approach will allow me to identify the environmental factors selecting for a specific microbial composition, and characterize its emerging functional properties. I will pioneer the use of meta-proteomics in complex communities to identify the function of the dominant microorganisms, and elucidate the underlying metabolic network. Finally, based on the acquired unique knowledge, I will develop a general, multi-species model to study metabolic interactions in denitrifying communities as well as the role of denitrification itself in complex ecosystems. The proposed research builds on my strong multidisciplinary background, from bioreactors and mathematical modelling to advanced microbiological techniques, and is driven by my absolute fascination for microbial metabolisms and their enormous and largely unexploited potential to benefit society at large.
Netherlands