Sarah Lydia Lebeis

###Education
B.S., 2002, Michigan State University
Ph.D., 2008, Emory University
Postdoctoral Fellow, 2009-2014, University of North Carolina, Chapel Hill

###Research
Plants have evolved in a microbial world and, as with many other multicellular organisms, they assemble a specific and robust subset of microorganisms into symbiotic communities. My lab aims to uncover how plants and microbes each contribute to host microbiome assembly. Although we study these aspects in the model system Arabidopsis thaliana, we also investigate several other systems to extend the importance of our findings. Understanding mechanisms of plant microbiome assembly and function will be critical as we move from basic lab experiments into development of plant biological products with significant impact on improving food production to meet increasing global demands.

Plant influence over microbiome composition

Chemicals exuded by roots are predicted to drive microbial recruitment toward positive factors and microbial susceptibility to negative factors. The current work in my lab focuses on 1) microbial chemotaxis toward positive factors in the root exudates, such as sugars, and 2) microbial survival despite the presence of negative growth factors, such as phenolic compounds made by the plant immune system.

Critical microbe-microbe interactions in plant microbiome assembly

When the root microbiome was determined for several plants grown in a common soil source, host genotype did not fully explain the differences, suggesting other influencing factors such as microbe-microbe interactions. Although the mechanisms of plant microbiome assembly and stability are likely complicated and interweaving, my lab has selected to study microbe-microbe interactions on two specific examples: 1) the impact of Streptomyces on other microbes in the root microbiome and 2) construction of a series of individual strain drop-out synthetic community experiments.

Together the results generated in my lab helps to define the mechanisms of how plants and microbes interact to impact plant microbiome assembly, but also more broadly how a host harnesses the complex microbial inoculum in which it lives.