Bharti Yadav

A new theory for the design and engineering of a stable two species microbial community

Microbial communities play a key role in human health [1,2], biotechnology [3,4], geochemical cycles and the environment [5,6]. Several theories have been proposed to understand the stability of microbial communities [7-9]. The theories have limitations. For instance, they are unable to explain the limited success of faecal transplantation or the restoration of gut microbiomes using probiotics. A key limitation of the theories is that they predict the stability of communities based on the net interactions between species pairs [10,11]. Microbial species in a community are considered to interact via pairwise interactions. These net interactions are composed of positive and negative components, which the current theories ignore, limiting their predictive ability [12]. Here, we propose a new theory explicitly incorporating the positive and negative interaction components. The species populations are assumed to evolve according to the Lotka-Volterra population dynamics model. We have conducted an analysis on the stability of a two species microbial community, incorporating only negative interactions, using linear stability analysis. Our findings enable us to forecast varying stability within the system based on different resource intake scenarios as well as different underlying components. Further, We discuss this approach can be generalised to multi-specices microbial communities and can be used to formulate better faecal transplantation or the restoration of gut microbiomes using probiotics.

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