Adaptability of non-genetic diversity in bacterial chemotaxis
Abstract
Bacterial chemotaxis systems are as diverse as the environments that bacteria inhabit, but how much environmental variation can cells tolerate with a single system? Diversification of a single chemotaxis system could serve as an alternative, or even evolutionary stepping-stone, to switching between multiple systems. We hypothesized that mutations in gene regulation could lead to heritable control of chemotactic diversity. By simulating foraging and colonization of Escherichia coli using a single-cell chemotaxis model, we found that different environments selected for different behaviors. The resulting trade-offs show that populations facing diverse environments would ideally diversify behaviors when time for navigation is limited. We show that advantageous diversity can arise from changes in the distribution of protein levels among individuals, which could occur through mutations in gene regulation. We propose experiments to test our prediction that chemotactic diversity in a clonal population could be a selectable trait that enables adaptation to environmental variability.
Article and author information
Author details
Reviewing Editor
- Eve Marder, Brandeis University, United States
Version history
- Received: May 30, 2014
- Accepted: September 28, 2014
- Accepted Manuscript published: October 3, 2014 (version 1)
- Version of Record published: October 28, 2014 (version 2)
Copyright
© 2014, Frankel et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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