Discipline: Biological Sciences
Subcategory: Environmental Engineering
Coty Weathersby - University of Wisconsin-Madison
Nitrification has traditionally been viewed as a two-step process where ammonium is oxidized to nitrite via ammonium oxidizing bacteria (AOB), and nitrite is oxidized to nitrate via nitrite oxidizing bacteria (NOB). There has always been a heavy focus on AOB as they have been considered the rate-limiting step in nitrification. NOB are of biotechnological interest because they are metabolically versatile and not limited to oxidizing nitrite exclusively. Aerobic conditions give the traditional case where the electron donor is nitrite and the electron acceptor is oxygen. In anoxic environments, NOB will utilize alternate electron donors (formate, hydrogen gas) to reduce nitrate. This research looks to build a genome-scale model (GEM) of Nitrospira moscoviensis by defining and determining the metabolic reactions that occur within the organism. The stoichiometric ratios of these reactions are transformed into a matrix to build the mathematical representation of the GEM. The GEM will be used to examine the extent to which NOB benefit from alternative metabolisms and simulate how NOB respond to changes in substrates (formate, hydrogen gas, nitrite) and electron acceptor (oxygen gas, nitrate) availability. Metabolic flux analysis based on experimental metabolomics measurements will also be used to validate the GEM.
Funder Acknowledgement(s): NSF (CBET-1435661 and MCB-1518130)
Faculty Advisor: Christopher Lawson, email@example.com
Role: Model simulations; Metabolite extractions; Bioreactor operation