Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1981 Jan;78(1):464-8.
doi: 10.1073/pnas.78.1.464.

Osmotic control of kdp operon expression in Escherichia coli

L A Laimins, D B Rhoads, W Epstein

Osmotic control of kdp operon expression in Escherichia coli

L A Laimins et al. Proc Natl Acad Sci U S A. 1981 Jan.

Abstract

Turgor pressure, the difference in osmotic pressure across the inner membrane, has been found to regulate expression of the kdp operon in Escherichia coli. The kdp operon codes for a high-affinity repressible transport system for the uptake of potassium. We have studied the regulation of Kdp expression in a strain in which the gene for beta-galactosidase, lacZ, was placed under control of the kdp promotor. Neither internal nor external K+ concentrations directly controlled Kdp expression. Only when the external K+ concentration was reduced to the point of limiting growth was the kdp operon expressed. An increase in external osmolarity at constant K+ concentration, a procedure that reduces turgor pressure, caused expression of the kdp operon. As the magnitude of the osmotic shift was increased, corresponding to greater decreases in turgor pressure, the amount of Kdp expression also increased. The kdp operon thus appears to be controlled by changes in a physical force, the turgor pressure.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. J Mol Biol. 1967 Dec 28;30(3):529-43 - PubMed
    1. J Bacteriol. 1970 Mar;101(3):836-43 - PubMed
    1. J Bacteriol. 1971 Nov;108(2):639-44 - PubMed
    1. J Gen Physiol. 1976 Mar;67(3):325-41 - PubMed
    1. J Biol Chem. 1977 Feb 25;252(4):1394-401 - PubMed

Publication types

LinkOut - more resources