Analysis of hydrostatic pressure effects on transcription in Escherichia coli by DNA microarray procedure.

Hydrostatic pressure is a well-known physical stimulus, but its effects on cell physiology have not been clarified. To investigate pressure effects on Escherichia coli, we carried out DNA microarray analysis of the entire E. coli genome. The microarray results showed pleiotropic effects on gene expression. In particular, heat- and cold-stress responses were induced simultaneously by the elevated pressure. Upon temperature stress (including both temperature up- and down-shifts) and other environmental stresses, gene expression adjusts to adapt to such environmental changes through regulations by several DNA-binding proteins. An E. coli mutant, which deleted the hns gene encoding one of the regulator proteins, exhibited great pressure sensitivity. The result suggested that the H-NS protein was a possible transcriptional regulator for adaptation of the high-pressure stress.