Back to Search
Start Over
γ-proteobacteria eject their polar flagella under nutrient depletion, retaining flagellar motor relic structures.
- Source :
-
PLoS Biology . 3/19/2019, Vol. 17 Issue 3, p1-25. 25p. 2 Color Photographs, 2 Black and White Photographs, 1 Diagram, 2 Charts, 1 Graph. - Publication Year :
- 2019
-
Abstract
- Bacteria switch only intermittently to motile planktonic lifestyles under favorable conditions. Under chronic nutrient deprivation, however, bacteria orchestrate a switch to stationary phase, conserving energy by altering metabolism and stopping motility. About two-thirds of bacteria use flagella to swim, but how bacteria deactivate this large molecular machine remains unclear. Here, we describe the previously unreported ejection of polar motors by γ-proteobacteria. We show that these bacteria eject their flagella at the base of the flagellar hook when nutrients are depleted, leaving a relic of a former flagellar motor in the outer membrane. Subtomogram averages of the full motor and relic reveal that this is an active process, as a plug protein appears in the relic, likely to prevent leakage across their outer membrane; furthermore, we show that ejection is triggered only under nutritional depletion and is independent of the filament as a possible mechanosensor. We show that filament ejection is a widespread phenomenon demonstrated by the appearance of relic structures in diverse γ-proteobacteria including Plesiomonas shigelloides, Vibrio cholerae, Vibrio fischeri, Shewanella putrefaciens, and Pseudomonas aeruginosa. While the molecular details remain to be determined, our results demonstrate a novel mechanism for bacteria to halt costly motility when nutrients become scarce. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 15449173
- Volume :
- 17
- Issue :
- 3
- Database :
- Academic Search Index
- Journal :
- PLoS Biology
- Publication Type :
- Academic Journal
- Accession number :
- 135422836
- Full Text :
- https://doi.org/10.1371/journal.pbio.3000165