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Monitoring Intraspecies Competition in a Bacterial Cell Population by Cocultivation of Fluorescently Labelled Strains
Published on: January 18, 2014
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Suboptimal resource allocation in changing environments constrains response and growth in bacteria
Rohan Balakrishnan1, Roshali T de Silva2, Terence Hwa1,3
1Department of Physics, University of California at San Diego, La Jolla, CA, USA.
Molecular Systems Biology
|December 20, 2021
Summary
Microbes manage depleting precursors during fluctuating conditions by expressing non-essential genes, hindering optimal growth. This reveals hardwired microbial strategies, not growth optimization, in changing environments.
Area of Science:
- Microbial physiology
- Systems biology
- Gene expression regulation
Background:
- Microbes require novel protein synthesis to adapt to environmental changes.
- Protein synthesis depends on sufficient biosynthetic precursors.
- Effective precursor management is crucial for microbial survival and adaptation.
Purpose of the Study:
- To investigate Escherichia coli's active response to changing nutrient conditions.
- To connect transient gene expression dynamics with cellular growth phenotypes.
- To understand how limited protein synthesis capacity constrains microbial responses.
Main Methods:
- Synthetic modification of gene expression in Escherichia coli.
- Analysis of transient gene expression patterns.
- Correlation of gene expression with growth phenotypes under fluctuating conditions.
Main Results:
- Competition for limited protein synthesis capacity constrains cellular responses.
- Cells express non-essential genes, leading to low precursor levels.
- This gene expression strategy hinders precursor replenishment, indicating sub-optimal growth.
Conclusions:
- Microbial responses to changing environments are hardwired, not optimized for growth.
- These strategies may promote fitness in native environments.
- Findings offer a framework for predicting evolution and improving biotechnological gene circuits.
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