Linked Life Data

8117683

Source:http://linkedlifedata.com/resource/pubmed/id/8117683

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1994-4-4
pubmed:abstractText
The interactions of transcription inhibitors with the open complex composed of Escherichia coli RNA polymerase and the lacUV5 promoter have been studied using gel retardation, the chemical nuclease activity of the cuprous complexes of 1,10-phenanthroline (OP) and its derivatives, and steady-state kinetics. Gel retardation shows that two inhibitors, the 2:1 2,9-dimethyl-1,10-phenanthroline-cuprous complex [(2,9-Me2OP)2Cu+] and rifampicin, bind stably to the open-complex. (2,9-Me2OP)2Cu+ blocks scission by the chemical nuclease by interfering with the binding of its redox-active isosteres. Rifampicin does not block scission by the cuprous complexes of 3,4,7,8-tetramethyl-OP, 4-phenyl-OP, and OP but does perturb scission by the cuprous complex of 5-phenyl-OP. Organic ligands including intercalating agents and groove binders (e.g., daunomycin, di(amidinophenyl)indole (DAPI), actinomycin D, distamycin, 9-aminoacridine, mithramycin, and chromomycin A3), which bind to free DNA with high affinity, do not form stable ternary complexes with the open-complex. Gel retardation experiments demonstrate that they promote dissociation of the enzyme from the promoter. The greater sensitivity of enzymatic catalysis to inhibitor concentration relative to polymerase binding suggests that these ligands form metastable, catalytically inactive ternary complexes with RNA polymerase and the promoter.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
33
pubmed:geneSymbol
lacUV5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2262-8
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Interactions of transcription inhibitors with the Escherichia coli RNA polymerase-lacUV5 promoter open complex.
pubmed:affiliation
Department of Biological Chemistry, School of Medicine, University of California-Los Angeles 90024-1570.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't