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06:01
Standardized Methods for Measuring Induction of the Heat Shock Response in Caenorhabditis elegans
Published on: July 3, 2020
Cold shock induces qnrA expression in Shewanella algae.
Hong Bin Kim1, Chi Hye Park, Mariah Gavin
1Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
Antimicrobial Agents and Chemotherapy
|November 17, 2010
Summary
Cold shock increases the expression of quinolone resistance gene (qnrA) in Shewanella algae. This suggests qnrA may help bacteria adapt to colder environments.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Plasmid-mediated quinolone resistance genes, such as qnrA, are prevalent in Enterobacteriaceae.
- The native functions of these resistance genes are not well understood.
Purpose of the Study:
- To investigate the environmental factors influencing the expression of chromosomal qnrA in Shewanella algae.
- To understand the potential role of qnrA in bacterial adaptation.
Main Methods:
- Quantitative reverse transcription-PCR (qRT-PCR) was used to measure gene expression.
- Shewanella algae were exposed to various environmental conditions including DNA damage, oxidative stress, osmotic stress, starvation, heat, and cold shock.
Main Results:
- Only cold shock significantly increased chromosomal qnrA gene expression in Shewanella algae.
- The induction of qnrA expression was dose-dependent and occurred during growth arrest.
Conclusions:
- Cold shock induces qnrA expression in Shewanella algae.
- The qnrA gene may play a role in the adaptation of Shewanella to low-temperature environments.
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