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Updated: Jul 11, 2025
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Extraction and Visualization of Protein Aggregates after Treatment of Escherichia coli with a Proteotoxic Stressor
Published on: June 29, 2021
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Protein aggregates act as a deterministic disruptor during bacterial cell size homeostasis
Julien Mortier1, Sander K Govers1,2, Alexander Cambré1
1Department of Microbial and Molecular Systems, KU Leuven, Leuven, Belgium.
Cellular and Molecular Life Sciences : CMLS
|November 16, 2023
Summary
Protein aggregates cause deterministic cell size differences in bacteria. This asymmetric division, observed in Escherichia coli and Bacillus subtilis, results from altered cell division positioning.
Area of Science:
- Bacterial cell division
- Microbiology
- Cell biology
Background:
- Cell size variation among clonal bacterial siblings is typically viewed as random.
- Intracellular protein aggregates (PAs) are known to form in bacteria under stress.
Purpose of the Study:
- To investigate the mechanisms behind cell size fluctuations in heat-stressed bacteria.
- To determine if intracellular protein aggregates influence bacterial cell division and size.
Main Methods:
- Microscopy of heat-stressed Escherichia coli and Bacillus subtilis populations.
- Analysis of cell division septum positioning and cell length.
- Investigation of the physical interaction between protein aggregates and cellular structures.
Main Results:
- A polar protein aggregate (PA) was found to cause deterministic asymmetry in cell division.
- PA presence leads to off-center positioning of the FtsZ division septum.
- PA-inheriting daughter cells exhibit increased length persisting over generations.
Conclusions:
- Intracellular protein aggregates induce asymmetric cell division in bacteria.
- Protein aggregates can physically perturb the nucleoid, leading to asymmetric septation.
- This mechanism provides a deterministic basis for cell size variation in bacterial populations.
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