Oliver Baars

Assistant Professor
Partners Building III, Room 223


We are interested in the interactions between microbes, primary producers (plants or phytoplankton), and the environment via secreted small molecules. Our goal is to reveal biological and chemical mechanisms that impact biogeochemical cycles, crop productivity, and human health. The vast majority of microbes cannot be cultured and analyzing the extreme complexity of mixtures of molecules with orders of magnitude differences in concentrations and activities is a challenge. Our studies make use of rapid developments in analytical instrumentation for profiling and characterizing relevant groups of secreted small molecules in an environmentally or agriculturally relevant context. Our working hypotheses start with an understanding of the importance of trace-metal limitation or toxicity as a bottom-up control on microbial communities and their interactions with plants or phytoplankton. For example, the role of iron as a limiting micro-nutrient can be observed in the oceans, in terrestrial environments, and in the struggle of pathogens to infect hosts. Our current research focuses on trace-metal regulated small-molecule interactions in the rhizosphere and their impact on nitrogen-fixation and plant growth. As part of our efforts, we study the structures, reactivity, and biology of secreted plant chelators and microbial siderophores in controlled laboratory incubations and natural environments using new molecular and elemental mass spectrometry approaches with chemical or spatial separations.


B. Sc. Chemistry, University of Leipzig
M. Sc. Chemistry, University of Leipzig
Ph. D. Chemistry, University of Kiel
Postdoc, Princeton University