Linked Life Data

3016284

Source:http://linkedlifedata.com/resource/pubmed/id/3016284

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1986-9-17
pubmed:abstractText
The mechanism by which the cyclic AMP receptor protein, CRP, stimulates transcription of the Escherichia coli araBAD promoter was studied in vitro. Under one set of conditions, CRP stimulated by eightfold the rate of RNA polymerase open complex formation on supercoiled DNA template containing the normal wild-type araBAD regulatory region. Since previous studies in vivo had identified an upstream site termed araO2 that is involved in both repression and in the CRP requirement for PBAD induction, we performed similar experiments in vitro. Deletion of araO2 or alterations of its orientation with respect to the araI site by half integral numbers of turns greatly reduced the CRP requirement for induction of PBAD. Linearizing the DNA has the same effect as deleting araO2 from the supercoiled DNA template. The similarity of conditions that relieve the classical repression of PBAD in vivo and the conditions that eliminate the requirement for CRP for maximal activity in vitro suggest a close relationship between repression in the ara system and the role of CRP. At lower concentrations of AraC protein and slightly different conditions than those used in the above-mentioned experiments, CRP does stimulate transcription from linear or supercoiled templates lacking araO2. On linear DNA under these conditions, one dimer of AraC protein binds to linear araPBAD DNA, but is incapable of stimulating transcription without the additional binding of CRP. The responses of the ara system under the second set of conditions are unlike its behavior in vivo.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
188
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
355-67
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Transcription of Escherichia coli ara in vitro. The cyclic AMP receptor protein requirement for PBAD induction that depends on the presence and orientation of the araO2 site.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.