Stochastic study of information transmission and population stability in a generic bacterial two-component system

TL;DR

This paper develops a stochastic theoretical framework to analyze noise and information transmission in bacterial two-component systems, revealing how fluctuations influence population stability and protein distribution.

Contribution

It introduces a novel stochastic model for bacterial two-component systems, highlighting the roles of phosphotransfer and feedback in noise propagation and population stability.

Findings

Phosphotransfer module enhances information transmission despite noise.

Bimodal protein distributions emerge due to fluctuations.

Identifies parameter regimes causing stability switches in protein levels.

Abstract

Studies on the role of fluctuations in signal propagation and on gene regulation in monoclonal bacterial population have been extensively pursued based on the machinery of two-component system. The bacterial two-component system shows noise utilisation through its inherent plasticity. The fluctuations propagation takes place using the phosphotransfer module and the feedback mechanism during gene regulation. To delicately observe the noisy kinetics the generic cascade needs stochastic investigation at the mRNA and protein levels. To this end, we propose a theoretical framework to investigate the noisy signal transduction in a generic two-component system. The model shows reliability in information transmission through quantification of several statistical measures. We further extend our analysis to observe the protein distribution in a population of cells. Through numerical simulation, we identify the regime of the kinetic parameter set that generates a stability switch in the steady state distribution of proteins. The results of our theoretical analysis show key features of the network. The noise permeation and information propagation in the autoregulation module is feeble. However, the phosphotransfer module compensates such weakness and plays a significant role in information transmission. The bimodality due to fluctuations pampers the emergence of persistence in an isogenic bacterial pool.