Medical/biological Study (experimental study)

Magnetic field exposure enhances mRNA expression of sigma 32 in E. coli. med./biol.

PubMed Entry

Journal web site

Aim of study (according to author)
To examine the stress response in Escherichia coli exposed to a magnetic field.
Background/further details:
The examined parameter was the transcription of Sigma 32 (σ³²), a protein that is essential for the transcription initiation of heat shock protein genes. It enhances the RNA polymerase binding probability to promoter sides on DNA. Therefore sigma 32 represents a good marker of stress response in Escherichia coli.

Endpoint

• stress response (mRNA level of protein sigma 32)

Exposure
General category: magnetic field, 50/60 Hz (AC)

Field characteristics	Parameters
60 Hz exposure duration: 15 min	magnetic flux density: 1.1 mT effective value

Exposed system:
bacterium (in vitro)
Escherichia coli/MG1655

Methods
Endpoint/Measurement parameters/Methodology

• molecular biosynthesis: mRNA level of protein sigma 32 (gel electrophoresis, RNAse Protection Assay, UV rays spectroscopy)

Main outcome of study (according to author)
The intracellular level of sigma 32 mRNA was significantly enhanced following the exposure to magnetic field.

(Study character: medical/biological study, experimental study, full/main study)

Study funded by

• not stated/none

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