PROJECT SUMMARY
Understanding communication among bacteria is a fundamental biological problem with critical
implications for public health, especially in the context of bacterial communities known as biofilms. While
bacteria are single-celled organisms, biofilms can exhibit many multicellular behaviors through
emergent coordination and dynamic cell-to-cell signaling. Such collective behaviors unique to biofilms
contribute to their ability to tolerate antibiotics and thrive in nearly any environment. While the advent of
next-generation sequencing has ushered in a new appreciation for the broad and ubiquitous roles of
bacteria in nature, our understanding of their molecular mechanisms of community coordination remains
in its infancy. My overarching goal is to understand how coordinated group behaviors arise in bacterial
biofilm communities through previously unexplored cell-to-cell signaling mechanisms, and how these
emergent behaviors impart functional community-level benefits. Specifically, over the next five years,
my group will use multiscale microscopy, high-throughput approaches, and quantitative genetics to
decipher how gene regulation, metabolic adaptation, and microenvironmental feedback give rise to
emergent coordination and multicellular behaviors in bacterial biofilms. With this MIRA award, my group
will explore these questions by focusing on model Bacillus subtilis biofilms, where we recently used a
multiscale microfluidic platform to discover that biofilm bacteria can engage in ion channel-mediated
electrochemical cell-to-cell signaling. This discovery, along with other unpublished phenomena
discovered by my group, make B. subtilis a powerful system for investigating how emergent behaviors
arise in bacterial biofilms from single-cell-level properties such as gene regulatory networks and
metabolic adaptation. Our data will inform quantitative models of multicellular phenomena, which will
give us a system-level understanding of multicellular behaviors in microbes, as well as suggesting new
ways to control biofilms.
