Effects of static magnetic field on cell growth, viability, and differential gene expression in Salmonella.

In the present study, we investigated the effect of exposure to A static magnetic field (SMF) on cell growth, viability, and gene expression of Salmonella enterica subsp. enterica serovar Hadar. Our results indicated that SMF exposure (200 mT, 13 hours) failed to alter cellular growth but induced a decrease of colony-forming units (CFU) between 3 and 6 hours followed by an increase from 6 to 9 hours. The analysis of the differential expression of rpoA, dnaK, katN, and 16S rRNA genes under SMF exposure (200 mT, 10 hours) showed that the expression level of the 16S rRNA mRNA remained stable during the exposure and can thus be used as a reference gene for the analysis on the differential gene expression of Salmonella Hadar. Interestingly, mRNAs of rpoA, katN, and dnaK genes were over-expressed following 10 hours of SMF exposure (200 mT). These data suggest a possible stress response of Salmonella Hadar to static magnetic field.