Jintao Liu, Rosa Martinez-Corral, Arthur Prindle, Dong-yeon D. Lee, Joseph Larkin, Marçal, Gabalda-Sagarra, Jordi Garcia-Ojalvo and Gürol M. Süel. Coupling between distant biofilms and emergence of nutrient time-sharing. Science, Abril 2017. DOI: 10.1126/science.aah4204.  

Abstract:

Bacteria within communities can interact to organize their behavior. It has been unclear whether such interactions can extend beyond a single community to coordinate the behavior of distant populations. We discovered that two Bacillus subtilis biofilm communities undergoing metabolic oscillations can become coupled through electrical signaling and synchronize their growth dynamics. Coupling increases competition by also synchronizing demand for limited nutrients. As predicted by mathematical modeling, we confirm that biofilms resolve this conflict by switching from in-phase to antiphase oscillations. This results in time-sharing behavior, where each community takes turns consuming nutrients. Time-sharing enables biofilms to counterintuitively increase growth under reduced nutrient supply. Distant biofilms can thus coordinate their behavior to resolve nutrient competition through time-sharing, a strategy used in engineered systems to allocate limited resources.

Time-lapse movie of in-phase oscillations in a pair of biofilms. The images show the edge of two wild-type biofilms grown in the same microfluidic chamber with continuous supply of 30 mM glutamate (1x). Cyan indicates fluorescence from the membrane potential dye ThT. The time-traces show ThT fluorescence (after detrending and normalization) from the corresponding biofilms. Source: UPF USCD.