Linked Life Data

7854119

Source:http://linkedlifedata.com/resource/pubmed/id/7854119

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1995-3-14
pubmed:abstractText
Expression from both the Escherichia coli nir and nrf promoters is dependent on anaerobic induction by FNR but is further regulated by NarL and NarP in response to the presence of nitrite and nitrate in the growth medium. The nir promoter is activated by NarL in response to nitrate and nitrite and activated by NarP in response to nitrate but not nitrite. The effects of point mutations suggest that NarL and NarP both bind to the same target, which is a pair of heptamer sequences organized as an inverted repeat, centred 69 1/2 bp upstream of the transcript startpoint. The nrf promoter can be activated by either NarP or NarL in response to nitrite but is repressed by NarL in response to nitrate. Mutational analysis of the nrf promoter has been exploited to corroborate the location of the -10 hexamer and the FNR-binding site, and to find the sites essential for nitrite-dependent activation and nitrate-dependent repression. Optimal activation by NarP or NarL in response to nitrite requires an inverted pair of heptamer sequences, similar to that found at the nir promoter, but centred 74 1/2 bp upstream from the transcript start. NarL-dependent repression by nitrate is due to two heptamer sequences that flank the FNR-binding sequence. We conclude that NarL and NarP bind to the same heptamer sequences, but that the affinities for the two factors vary from site to site.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0950-382X
pubmed:author
pubmed:issnType
Print
pubmed:volume
13
pubmed:geneSymbol
fnr, narL, narP, nrf, pnrf
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1045-55
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Nitrite and nitrate regulation at the promoters of two Escherichia coli operons encoding nitrite reductase: identification of common target heptamers for both NarP- and NarL-dependent regulation.
pubmed:affiliation
School of Biochemistry, University of Birmingham, Edgbaston, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't