Microbial social interactions
Social traits in microbes include cooperation to perform activities such as dispersal, foraging, construction of biofilms, reproduction, chemical warfare and signalling. However, a selfish 'cheater' bacterium that arises from mutation can reproduce and thrive at the expense of the cooperating population. Manipulating such phenomena can help in fostering or disrupting bacterial cooperation. Applications include tackling infections as well as enhancing efficiency of industrial processes involving microorganisms. The SOCMICROECO (Social evolution in microbial ecosystems) project combined theory and experiments to develop a predictive framework of emerging social interactions in a system containing five bacteria that digest metal-working fluids (MWFs). SOCMICROECO researchers have completed research on general theoretical predictions concerning social interactions between microbes and this has been published in the prestigious Annual Review of Genetics. Applying the predictions, the team worked out the frequencies of microbes with different social traits at equilibrium. Importantly, SOCMICROECO have set up the complete experimental system for study of the five MWF digesting bacteria. Results so far have revealed features that may influence interactions including differing growth rates and biofilm production. The team have also devised a simple model that can be used to describe the growth of multiple species in co-culture. Using data from microbes in cheese rind indicated that most inter-species interactions were weak. Moreover, none of the species pairs showed mutually cooperative growth patterns. Members of the consortium will continue to study and disentangle the interactions between the species for treatment of MWFs. Final results stand to be important in achieving the right dynamics for the most efficient way to deal with pollutants of this nature. Using a standard model for input of data, the applications could be extended to other microbial ecosystems for efficient waste treatment and biomedicine.
Keywords
Microbe, computer model, social interaction, infection, metal-working fluid, waste treatment, biomedicine
