Linked Life Data

3511843

Source:http://linkedlifedata.com/resource/pubmed/id/3511843

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1986-3-12
pubmed:abstractText
Fluorescence excited-state energy transfer measurements were carried out between the N-(1-pyrene)maleimide (PM)-labeled sigma subunit and Co in the beta subunit of Co-Zn RNA polymerase (RPase). sigma subunit with or without PM labeling was cleaved with 2-nitro-5-thiocyanobenzoic acid, and the reaction products were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. One molecule of the fluorescent probe (PM) was found to be attached to the cysteine-132 residue of the sigma subunit. When excited at 340 nm, the fluorescence emission bands from 380 to 420 nm of PM-labeled sigma overlap with the charge transfer absorption band of Co-Zn RPase around 400 nm. Based on Förster's equation, the R0 values for the donor-acceptor pair were calculated to be 21.5 and 22 A in the absence and presence of template analog (dA-dT)60, respectively. Using these R0 values and the observed energy transfer efficiencies, the distance between the cysteine-132 of the sigma subunit and Co located at the initiation site of the beta subunit was calculated to be 22 A with or without the template present, indicating that no major conformational change of the enzyme was induced upon template binding. However, a small but significant change in the above distance was observed upon the addition of ATP to RPase in the presence (dA-dT)60 but not in the absence of (dA-dT)60 template. The biological implications of these observations are discussed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:volume
244
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
218-25
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Spatial relationship between the intrinsic metal in the beta subunit and cysteine-132 in the sigma subunit of Escherichia coli RNA polymerase: a resonance energy transfer study.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.