Scialog: Collaborative Teams - 2017
A tunable microfluidic platform for observing long-term microbial community dynamics
There is still much to understand about the dynamics of bacterial communities in the human gut, as well as how bacteria behave en mass in a biofilm, a collective of microorganisms that can grow on many different surfaces. (A common form of biofilm is dental plaque, the slimy buildup of bacteria on teeth.)
To better understand long-term microbial community dynamics, a team of three scientists – Roy Dar, University of Illinois at Urbana Champaign; Brian Hammer, Georgia Tech; and Srividya Iyer-Biswas, Purdue University -- is working with $168,750 in funding received through Scialog: Molecules Come to Life, an initiative cosponsored by Research Corporation for Science Advancement (RCSA) and the Gordon and Betty Moore Foundation. Scialog encourages early career scientists to form multidisciplinary teams to identify and tackle critical research challenges.
The team will attempt to establish a spatially and temporally “tunable” microfluidic platform for studying the dynamics of cooperation and conflict between two interacting bacteria populations in a biofilm. Specifically, they aim to harness “quorum sensing” (QS), or cell-to-cell signaling, abilities of the bacterium Vibrio cholerae. Quorum sensing is a process that allows bacterial cells in a community to cooperate by synchronously expressing sets of genes in response to self-produced chemical signals that accumulate in the environment. The Vibrio microbe can cause fatal disease by thriving in the human gut, and has recently been shown to kill adjacent competitor bacteria by piercing them with a toxin-tipped nanoweapon, called a Type 6 Secretion System (T6SS).
The researchers will create a microfluidic device and reengineered Vibrios that activate genes for the nanoweapon only in response to QS signals that are made by competitors, rather than self-produced. The team predicts the coupling of cooperation by QS to conflict mediated by the T6SS weapon will lead to predictable oscillations in the spatial organization of the mixed biofilm community. They will also develop mathematical models to characterize the interactions occurring between the bacterial community members.
Because their work involves biofilms produced by a disease-causing microbe, this study could have important implications for industrial, environmental and human health issues.