Linked Life Data

2453279

Source:http://linkedlifedata.com/resource/pubmed/id/2453279

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1988-6-29
pubmed:abstractText
Using purified DNA gyrase to supercoil circular plasmid pBR322 DNA, we examined how the linking number attained at the steady state ('static head') varies with the concentrations of ATP and ADP, both in the absence and presence of spermidine. In the absence of spermidine at total adenine nucleotide concentrations between 0.35 and 1.4 mM, the static-head linking number was independent of the sum concentration of ATP and ADP, but depended strongly on the ratio of their concentrations. We established that the same linking number was attained independent of the direction from which the steady state was approached. The decrease in linking number at static head is more extensive when spermidine is present in the incubation, but remains a function of the [ATP]-to-[ADP] ratio. These results are discussed in terms of various kinetic schemes for DNA gyrase. We present one kinetic scheme that accounts for the experimental observations. According to this scheme our experimental results imply that there is significant slip in DNA gyrase when spermidine is absent. It is possible that spermidine acts through adjustment of the degree coupling of DNA gyrase.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0163-4992
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
157-81
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:articleTitle
DNA supercoiling by DNA gyrase. A static head analysis.
pubmed:affiliation
Laboratory of Molecular Biology, National Institute of Diabetes, and Digestive and Kidney Diseases, Bethesda, MD 20892.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't