Cs+ Induces the kdp Operon of Escherichia coli by Lowering the Intracellular K+ Concentration

AUTOR(ES)

Jung, Kirsten

FONTE

American Society for Microbiology

RESUMO

Cs+ was found to induce expression of the kdpFABC operon, encoding a high-affinity K+ uptake system of Escherichia coli. Quantitative expression analyses at the transcriptional and translational levels reveal that CsCl causes much higher induction of kdpFABC than does NaCl. A decrease of the intracellular K+ concentration is found in cells exposed to CsCl. The results indicate that kdpFABC expression is induced when the intracellular K+ concentration is lowered. Moreover, the results imply that the signal transduction cascade mediated by KdpD and KdpE is able to integrate multiple signals.

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