Transcription profiling of E. coli in response to ionic and non-ionic osmotica

ABSTRACT: Bacteria respond to osmotic stress by a substantial increase in the intracellular osmolality, adjusting their cell turgor for altered growth conditions. Using E. coli as a model organism we demonstrate here that bacterial responses to hyperosmotic stress specifically depend on the nature of osmoticum used. We show that increasing acute hyperosmotic NaCl stress above ~1.0 Os kg-1 causes a dose-dependent K+ leak from the cell, resulting in a substantial decrease in cytosolic K+ content and a concurrent accumulation of Na+ in the cell. At the same time, isotonic sucrose or mannitol treatment (non-ionic osmotica) results in a gradual increase of the net K+ uptake. Ion flux data is consistent with growth experiments showing that bacterial growth is impaired by NaCl at the concentration resultin

ORGANISM(S): Escherichia coli

SUBMITTER: John Phillip Bowman 

PROVIDER: E-GEOD-12190 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress