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Evidence of defined temporal expression patterns that lead a gram-negative cell out of dormancy
Nandhini Ashok1, Carl E Bauer2
1Department of Biology, Indiana University, Bloomington, Indiana, United States of America.
Plos Genetics
|March 24, 2020
Summary
Gram-negative bacteria R. centenum cysts germinate into two motile cells by activating specific gene expression patterns for protein synthesis, energy generation, and motility.
Area of Science:
- Microbiology
- Bacterial Physiology
- Cellular Dormancy
Background:
- Many bacteria form dormant cells like spores and cysts for survival.
- Gram-positive bacterial spores are well-studied, but Gram-negative cyst germination is poorly understood.
Purpose of the Study:
- To investigate the molecular mechanisms and gene expression dynamics during the germination of R. centenum cysts, a Gram-negative organism.
- To elucidate how Gram-negative bacteria emerge from dormancy.
Main Methods:
- Time-lapse transcriptomic analysis of R. centenum during cyst germination.
- Induction of cyst germination and observation of cellular changes.
Main Results:
- R. centenum cysts germinate into two motile vegetative cells within approximately 6 hours.
- Germination involves a temporal cascade of gene expression: protein synthesis, membrane potential generation, cell wall modification, DNA replication, metabolic pathway activation (TCA cycle, oxidative phosphorylation), and finally, photosystem and motility apparatus development.
Conclusions:
- Cyst germination in R. centenum is a highly regulated process with a defined temporal gene expression program.
- This study provides novel insights into the emergence of Gram-negative bacteria from dormancy, highlighting key molecular events.
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