Linked Life Data

776624

Source:http://linkedlifedata.com/resource/pubmed/id/776624

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1976-9-2
pubmed:abstractText
The subunit composition of Escherichia coli RNA polymerase during the transcription in vitro of bacteriophage T7DNA was analysed at several steps of RNA synthesis. RNA-polymerase . DNA complexes were sedimented through a glycerol gradient and the RNA polymerase subunits present in each fraction of the gradient were separated by dodecylsulfate-polyacrylamide gel electrophoresis and quantified colorimetrically on the gels. RNA polymerase selectively bound to T7 DNA in the absence of nucleoside triphosphates has the same subunit composition as free RNA polymerase holoenzyme (beta'betaalpha2) omicron. Addition of the nucleoside triphosphate combinations ATP, GTP, UTP or ATP, CTP, UPT, or GTP, CTP UTP to the binding reaction does not alter the subunit composition of RNA polymerase holenzyme bound to DNA. In contrast, in the presence of ATP, GTP and CTP up to 3 pmol of omicron-subunit are released from a complex containing RNA polymerase and 1 pmol of T7 DNA. In the presence of the four nucleoside triphosphates about 90% of the RNA polymerase associated with DNA and nascent RNA has the subunit composition of RNA polymerase core enzyme (bet'betaalpha2). The omicron-subunit is released from the complex and is recovered near the top of the gradient. The transition from the binding complex to the elongation complex and the incorporation of gamma32P-labeled ATP and GTP at the 5' end of RNA molecules were followed in parallel. In the purified elongation complex about 1 pmol of ATP or GTP is incorporated into RNA per pmol RNA polymerase core enzyme engaged in RNA synthesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
65
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
147-53
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
Subunit composition of Escherichia coli RNA polymerase during transcription in vitro.
pubmed:publicationType
Journal Article