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Published on: April 8, 2016
Twitching motility in Legionella pneumophila
1Laboratory of Bacteriology, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Leuven, Belgium.
FEMS Microbiology Letters
|February 27, 2009
Summary
Legionella pneumophila exhibits twitching motility, a bacterial movement using type IV pili. This motility is influenced by environmental factors and temperature, with a pilE mutant showing altered behavior.
Area of Science:
- Microbiology
- Bacterial Motility
- Type IV Pili
Background:
- Twitching motility is a surface translocation mechanism used by bacteria.
- Type IV pili mediate twitching motility and are involved in various bacterial processes including virulence and biofilm formation.
- Legionella pneumophila is the causative agent of Legionnaires' disease.
Purpose of the Study:
- To characterize twitching motility in Legionella pneumophila.
- To investigate the environmental factors influencing twitching motility in this bacterium.
- To analyze the role of the pilE gene in twitching motility.
Main Methods:
- Culturing Legionella pneumophila on agar plates with varying conditions.
- Observing and measuring twitching motility zones.
- Generating and testing a pilE knockout mutant.
Main Results:
- Twitching motility in L. pneumophila is significantly affected by agar concentration, media composition, charcoal, cysteine, bacterial proximity, and temperature.
- A pilE knockout mutant completely lost twitching motility at 37°C but retained it at 27°C.
- The differential effect of the pilE mutation at different temperatures suggests potential alternative mechanisms for twitching motility.
Conclusions:
- Environmental factors play a crucial role in modulating twitching motility in Legionella pneumophila.
- The pilE gene is essential for twitching motility at 37°C, but not at 27°C.
- Legionella pneumophila may possess alternative systems or pilus subunits that compensate for pilE function at lower temperatures.
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