Massively parallel screening of synthetic microbial communities

Significance Microbial communities have many applications, but current experimental strategies to investigate their behavior are limited by the combinatorial complexity of interactions between species. Here, we introduce a platform to automatically construct and test synthetic communities of microbes from a set of input species at a scale of ∼100,000 communities per day. As a first demonstration, we discovered specific compositions of bacteria isolated from local soil that promote the growth of a model plant symbiont. More broadly, our platform can be adopted for the discovery of microbial consortia with many useful properties, such as suppression of pathogens or degradation of recalcitrant substrates for use in biofuel production or environmental remediation.