Noise enhanced persistence in a biochemical regulatory network with feedback control

TL;DR

This paper demonstrates that discrete noise in biochemical feedback systems can significantly delay molecule extinction, revealing limitations of reaction rate equations in predicting molecule numbers.

Contribution

It introduces a stochastic analysis showing noise effects on plasmid persistence, highlighting discrepancies with deterministic models.

Findings

Discrete noise delays plasmid extinction

Reaction rate equations may fail to predict molecule numbers

Noise effects are significant even at large molecule counts

Abstract

We find that discrete noise of inhibiting (signal) molecules can greatly delay the extinction of plasmids in a plasmid replication system: a prototypical biochemical regulatory network. We calculate the probability distribution of the metastable state of the plasmids and show on this example that the reaction rate equations may fail in predicting the average number of regulated molecules even when this number is large, and the time is much shorter than the mean extinction time.