A continuous-time decision-making model for bacterial growth via quorum sensing: Theory and evidence

Abstract

Quorum sensing is a communication mechanism used by bacteria to coordinate population density dependent collective behavior. In the particular case of bacterial growth, quorum sensing acts as a control mechanism that optimizes the trade-o between intrinsic growth rate and the maximum population size that the environment can sustain. Herein, a model for controlled bacterial growth via quorum sensing in continuous time is proposed. One of the main innovations of the proposed model relative to existing ones is to assume that Nature seeks to optimize the population level over time. The growth curve optimization is formulated as the maximization of a discounted objective function where the variable is the activation threshold for the quorum sensing mechanism. Numerical evidence suggests that this discounted objective function based on the growth curves is unimodal in the activation threshold. Growth curves obtained from analyzing experimental data match those predicted by the model.