Determining the efficacy of post-segregational killing systems in commensal Escherichia coli

In this paper, results show that the non-native Axe/Txe provides stability beyond the period for which the native, and more commonly used, Hok/Sok was effective. However, we show that the model with flow cytometry data alone produces large posteriors for some of the parameters. Without constraining the parameter space through carrying out other experiments, the model is incapable of adding much greater incite to these systems. One such experiment would be qPCR to determine the plasmid copy number for each strain which would allow us to constrain the parameter relating to probability of plasmid loss. As synthetic biological applications progress in to more complex environments, such as the mammalian gut, consideration for the stability of synthetic circuits becomes essential. We anticipate that the use of mathematical and statistical modelling will become increasingly useful to rationalise the design of synthetic circuits as more components become available, and to predict their function as the complexity of the target environment increases.