Abstract:

Ecosystem functionality depends on interactions among populations, of the same or different taxa, and these are not just the sum of pairwise interactions. Thus, know-how of the social interactions occurring in mixed-populations are of high interest, however they are commonly unknown due to the limitations posed in tagging each population. Our quick approach enables us to determine how the addition/absence of a particular species affects the net productivity of a microbial community and use this to select productive combinations, i.e. designate their social effect on a general community. Positive, neutral or negative assignations are applied to describe the social behaviour within the community by comparing fitness effects of the community against the individual strain. The studied model uses bacterial strains with diverse MTBE degradation/growth capacities. Our approach enabled the selection of a single consortium from a full combinatorial testing of 7 individual strains (triplicate tests of 127 combinations), of which Rhodococcus ruber EE6, Agrobacterium sp. MS2 and Paenibacillus sp. SH7 were termed appropriate candidates for an MTBE bioremediation biofilm-based technology. Overall, our work appoints social behaviours on individual strains in mixed-populations as well as offering a web-tool (BSocial http://m4m.ugr.es/BSocial.html) for analysing the community framework and thus, contributing to the study of social interactions in natural and synthetic habitats within the microbial ecology and engineering fields.