Issue 9, 2011

Small delay, big waves: a minimal delayed negative feedback model captures Escherichia coli single cell SOS kinetics

Abstract

Background: How exactly does an organism coordinate its responses to differing environmental conditions, especially when several responses and physiological priorities are potentially conflicting? Recently, single cell results have been published on the kinetics of the bacterial SOS response. Based on these, we construct a relatively simple mathematical model for the regulatory control of the mutagenic elements of the Escherichia coliDNA repair system. Methods: We employ one first order delay differential equation for the dynamics of the activation level of mutagenic gene repair and one first order ordinary differential equation for the dynamics of the level of DNA damage. After manual adjustment of parameters, our model qualitatively reproduces the UV dose dependent RecA expression peak occurrence, peak amplitude and peak timing. Parameter noise captures qualitatively the fluctuations observed in the experimental data. Quantitative agreement is achieved for timing of the three response peaks for different doses of UV. Conclusions: A delayed negative feedback is likely to play a primary role in the regulation of the E. coli mutagenic gene repair. The model presented in this paper is an example of how a delayed regulatory mechanism establishes control over a critical organismic response with negative secondary effects.

Graphical abstract: Small delay, big waves: a minimal delayed negative feedback model captures Escherichia coli single cell SOS kinetics

Supplementary files

Article information

Article type
Paper
Submitted
29 Mar 2011
Accepted
03 Jun 2011
First published
23 Jun 2011

Mol. BioSyst., 2011,7, 2599-2607

Small delay, big waves: a minimal delayed negative feedback model captures Escherichia coli single cell SOS kinetics

L. Hilbert, D. Albrecht and M. C. Mackey, Mol. BioSyst., 2011, 7, 2599 DOI: 10.1039/C1MB05122A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements