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
. 1986 Jun;83(11):3654-8.
doi: 10.1073/pnas.83.11.3654.

The DNA loop model for ara repression: AraC protein occupies the proposed loop sites in vivo and repression-negative mutations lie in these same sites

The DNA loop model for ara repression: AraC protein occupies the proposed loop sites in vivo and repression-negative mutations lie in these same sites

K Martin et al. Proc Natl Acad Sci U S A. 1986 Jun.

Abstract

Two sets of experiments have been performed to test the DNA loop model of repression of the araBAD operon of Escherichia coli. First, dimethyl sulfate methylation protection measurements on normally growing cells show that the AraC regulatory protein occupies the araI site in the presence and absence of the inducer arabinose. Similarly, the araO2 site is shown to be occupied by AraC protein in the presence and absence of arabinose; however, its occupancy by AraC is greatly reduced when araI and adjacent sequences are deleted. Thus, AraC protein binds to araO2 cooperatively with some other component of the ara system located at least 60 base pairs away. Second, the mutational analysis presented here shows that the DNA components required for repression of araBAD are araI, araO2, and perhaps the araBAD operon RNA polymerase binding site.

PubMed Disclaimer

References

    1. J Mol Biol. 1967 May 14;25(3):443-54 - PubMed
    1. J Bacteriol. 1977 Feb;129(2):948-58 - PubMed
    1. Nat New Biol. 1971 Oct 6;233(40):166-70 - PubMed
    1. Genetics. 1971 Nov;69(3):289-302 - PubMed
    1. J Biol Chem. 1974 May 10;249(9):2946-52 - PubMed

Publication types

LinkOut - more resources