Linked Life Data

796665

Source:http://linkedlifedata.com/resource/pubmed/id/796665

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1977-3-15
pubmed:abstractText
In vitro transcription of the trp operon in isolated nucleoids from Escherichia coli was studied. RNA synthesis in this system occurred primarily as a continuation of transcription which had been initiated in vivo; little or no initiation of new RNA chains was observed. Transcription of the trp operon in nucleoids by endogenous RNA polymerase procedded efficiently and ceases sequentially in the order of the gene sequence within the operon. Under these conditions, no appreciable exonuccleolytic digestion of nascent 3H-RNA was found, though some endonucleolytic cleavage was generally seen. Little or no incorporation of 14C-leucine into polypeptides was observed, inspite of tha fact that considerable number of ribosomes and nascent RNA chains were found attached to the isolated nucleoids. The synthesis of trp mRNA continued in the presence of chloramphenicol or fusidic acid, or under conditions where the rebosomal translocation factor G was inactivated. From these and other kinetic studies of trp mRNA synthesis in nucleoids obtained from nonsense strong polar mutants of the trp operon, it was shown that transcription in nucleoids was not connected functionally with transloational processes and thus unable to exhibit polarity effected by a nonsense mutation or by general translational blockage. In studies employing nucleoids from nonsense strong polar mutants of the trp operon, it was demonstrated that RNA polymerase are scantily distributed over the region downstream from the nonsense mutation site of the operon, thereby supporting a notion that in vivo transcription is eventually terminated near the nonsense mutation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0026-8925
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
148
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
295-305
pubmed:dateRevised
2009-10-27
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
In vitro transcription of the tryptophan operon in isolated bacterial nucleoids.
pubmed:publicationType
Journal Article, In Vitro