EMF-Portal | Magnetic field exposure enhances mRNA expression of sigma 32 in E. coli

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

By: Cairo P, Greenebaum B, Goodman E

Published in: J Cell Biochem 1998; 68 (1): 1-7

Aim of study (acc. to author)

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

Exposure	Parameters
Exposure 1: 60 Hz Exposure duration: 15 min	magnetic flux density: 1.1 mT effective value

Exposure 1

Main characteristics

Frequency	60 Hz
Type	magnetic field
Waveform	sinusoidal
Exposure duration	15 min

Exposure setup

Exposure source	Helmholtz coils
Setup	Helmholtz coils mounted on a wooden frame; culture flasks placed in water-jacketed cylinder that was surrounded by the dual-filament-wound coils
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
magnetic flux density	1.1 mT	effective value	measured	-	-

Methods Endpoint/measurement parameters/methodology

Investigated system:

DNA/RNA

Time of investigation:

after exposure

Main outcome of study (acc. 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/no funding

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