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.

This work was in part supported by the San Diego Center for Systems Biology (NIH grant P50 GM085764), the National Institute of General Medical Sciences (grant R01 GM121888 to G.M.S.), the Defense Advanced Research Projects Agency (grant HR0011-16-2-0035 to G.M.S.), the Howard Hughes Medical Institute–Simons Foundation Faculty Scholars program (to G.M.S.), a Simons Foundation Fellowship of the Helen Hay Whitney Foundation (to A.P.), a Career Award at the Scientific Interface from the Burroughs Wellcome Fund (to A.P.), the Spanish Ministry of Economy and Competitiveness and FEDER (European Regional Development Fund) (project FIS2015-66503-C3-1-P, to J.G.-O.), the Generalitat de Catalunya (project 2014SGR0947, to J.G.-O.), the ICREA (Catalan Institution for Research and Advanced Studies) Academia program (to J.G.-O.), the “Maria de Maeztu” Programme for Units of Excellence in Research and Development (Spanish Ministry of Economy and Competitiveness, grant MDM-2014-0370 to J.G.-O.), the La Caixa foundation (to R.M.-C.), and a doctoral grant from the Formacion del Profesorado Universitario program of the Ministerio de Educacion, Cultura y Deportes, Spain (to M.G.-S.)