Linked Life Data

8045420

Source:http://linkedlifedata.com/resource/pubmed/id/8045420

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1994-8-31
pubmed:abstractText
We describe a new vector system for the in vitro construction of transcriptional fusions to the lacZ gene, which is expressed from the translational start signals of galK. The galK ribosome-binding site (RBS) and its natural preceding region ensure a constant efficiency for lacZ translation and, thus, the beta-galactosidase (beta Gal) production of a given fusion is directly proportional to the in vivo transcriptional activity of the inserted DNA fragment. Single-copy lambda prophage versions of multicopy constructs can be made by in vivo recombination. We use this system to compare the transcriptional activities of the promoters present in the dnaA-dnaN-recF-gyrB cluster. The order of strength of these promoters is gyrB > dnaA > recF > dnaN. It is assumed that gyrB belongs to the dnaA-dnaN-recF operon, because the short recF-gyrB intercistronic region does not contain a terminator. By using this new vector system, we have detected strong termination signals within recF that are functional even when recF is translated at its normal rate. The low level of transcription coming to the end of recF, and the highest activity of the gyrB promoter, as well as results obtained with several gyrB::lacZ translational fusions, support the conclusion that gyrB is predominantly expressed from its own promoter under standard growth conditions. Finally, we have found that transcription from the dnaA promoters is constant at different growth rates. This supports the idea that autoregulation of the dnaA gene is responsible for the coupling of the DnaA protein synthesis to cell mass increase, and accumulation of DnaA protein governs the initiation of chromosome replication.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0378-1119
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
145
pubmed:geneSymbol
dnaA, dnaN, gyrB, lacZ, recF
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
17-24
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
An improved vector system for constructing transcriptional lacZ fusions: analysis of regulation of the dnaA, dnaN, recF and gyrB genes of Escherichia coli.
pubmed:affiliation
Instituto de Investigaciones Citológicas, Fundación Valenciana de Investigaciones Biomédicas, Valencia, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't