Survival of the weakest in non-transitive asymmetric interactions among strains of E. coli

Michael J. Liao, Arianna Miano, Chloe B. Nguyen, Lin Chao, Jeff Hasty
2020 Nature Communications  
AbstractHierarchical organization in ecology, whereby interactions are nested in a manner that leads to a dominant species, naturally result in the exclusion of all but the dominant competitor. Alternatively, non-hierarchical competitive dynamics, such as cyclical interactions, can sustain biodiversity. Here, we designed a simple microbial community with three strains of E. coli that cyclically interact through (i) the inhibition of protein production, (ii) the digestion of genomic DNA, and
more » ... enomic DNA, and (iii) the disruption of the cell membrane. We find that intrinsic differences in these three major mechanisms of bacterial warfare lead to an unbalanced community that is dominated by the weakest strain. We also use a computational model to describe how the relative toxin strengths, initial fractional occupancies, and spatial patterns affect the maintenance of biodiversity. The engineering of active warfare between microbial species establishes a framework for exploration of the underlying principles that drive complex ecological interactions.
doi:10.1038/s41467-020-19963-8 pmid:33247128 fatcat:gtjbvyrsozfpboxnkus2cqzwnm