Ecological succession and the competition-colonization trade-off in microbial communities

Background During range expansion in spatially distributed habitats, organisms differ from one another in terms of their patterns of localization versus propagation. To exploit locations or explore the landscape? This is the competition-colonization trade-off, a dichotomy at the core of ecological succession. In bacterial communities, this trade-off is a fundamental mechanism towards understanding spatio-temporal fluxes in microbiome composition. Results Using microfluidics devices as structured bacterial habitats, we show that, in a synthetic two-species community of motile strains, Escherichia coli is a fugitive species, whereas Pseudomonas aeruginosa is a slower colonizer but superior competitor. We provide evidence highlighting the role of succession and the relevance of this trade-off in the community assembly of bacteria in spatially distributed patchy landscapes. Furthermore, aggregation-dependent priority effects enhance coexistence which is not possible in well-mixed environments. Conclusions Our findings underscore the interplay between micron-scale landscape structure and dispersal in shaping biodiversity patterns in microbial ecosystems. Understanding this interplay is key to unleash the technological revolution of microbiome applications.

Automated summary

This study used microfluidic devices to construct a synthetic community composed of two bacterial strains, and found that Escherichia coli is a fugitive species while Pseudomonas aeruginosa is a slower but superior competitor in spatially distributed patchy landscapes. The findings highlight the importance of succession and the trade-off between competition and colonization in the assembly of bacterial communities.