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Three-dimensional Imaging of Bacterial Cells for Accurate Cellular Representations and Precise Protein Localization
Published on: October 29, 2019
Going for baroque at the Escherichia coli K1 cell surface
Michael R King1, Susan M Steenbergen, Eric R Vimr
1Laboratory of Sialobiology, Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL 61802, USA.
Trends in Microbiology
|April 10, 2007
Summary
Bacterial phase variation generates extensive structural diversity in capsular polysialic acid. A single contingency locus, controlled by a translational switch on a prophage, drives this complex variation in Escherichia coli K1.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Phase variation typically involves stochastic switching between expressed and unexpressed phenotypes.
- Homopolysaccharide synthesis coupled with incomplete chemical modification can lead to extensive structural diversity.
Purpose of the Study:
- To analyze capsular polysialic acid (PSA) form variation in Escherichia coli K1.
- To identify the genetic mechanism controlling PSA structural diversity.
Main Methods:
- Analysis of capsular polysialic acid structures.
- Investigation of genetic control mechanisms in Escherichia coli K1.
Main Results:
- A single contingency locus controls the large number of variant PSA structures.
- A simple translational switch on a K1-specific prophage confers maximal structural diversity.
Conclusions:
- Escherichia coli K1 employs a mechanism of genetic parsimony to achieve extensive capsular polysaccharide variation.
- This strategy allows for significant structural diversity through a simple translational switch, offering evolutionary advantages.
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