Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1989 May;3(5):601-8.
doi: 10.1111/j.1365-2958.1989.tb00207.x.

FNR-dependent Repression of the Ndh Gene of Escherichia Coli and Metal Ion Requirement for FNR-regulated Gene Expression

Affiliations

FNR-dependent Repression of the Ndh Gene of Escherichia Coli and Metal Ion Requirement for FNR-regulated Gene Expression

S Spiro et al. Mol Microbiol. .

Abstract

The ndh gene of Escherichia coli which encodes an NADH dehydrogenase contains a putative FNR-binding site in its upstream non-coding region, and its expression has been investigated using an ndh-lacZ fusion. Expression of the fusion was found to be reduced during anaerobic growth, and experiments with hosts containing an fnr mutation and/or a multicopy fnr+ plasmid indicated that the anaerobic repression of the ndh gene is mediated by the FNR protein. Thus FNR can function as an anaerobic repressor as well as an anaerobic transcriptional activator. The results are consistent with the FNR-binding function attributed to the proposed consensus sequence. Using frdA- and ndh-lacZ fusions exhibiting positive and negative regulation by FNR, it was further shown that the depletion of metal ions in growth media with chelating agents mimics oxygen with respect to the activity of FNR. Possible roles for metal ions in the oxygen-sensing pathway associated with FNR function are discussed.

Similar articles

See all similar articles

Cited by 56 articles

See all "Cited by" articles

Publication types

MeSH terms

LinkOut - more resources

Feedback