Linked Life Data

2996588

Source:http://linkedlifedata.com/resource/pubmed/id/2996588

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
15
pubmed:dateCreated
1985-12-5
pubmed:abstractText
The influence of Escherichia coli single-strand binding (SSB) protein on the conformation and internal dynamics of pBR322 and pUC8 supercoiled DNAs has been investigated by using dynamic light scattering at 632.8 and 351.1 nm and time-resolved fluorescence polarization anisotropy of intercalated ethidium. SSB protein binds to both DNAs up to a stoichiometry that is sufficient to almost completely relax the superhelical turns. Upon saturation binding, the translational diffusion coefficients (D0) of both DNAs decrease by approximately 20%. Apparent diffusion coefficients (Dapp) obtained from dynamic light scattering display the well-known increase with K2 (K = scattering vector), leveling off toward a plateau value (Dplat) at high K2. For both DNAs, the difference Dplat - D0 increases upon relaxation of supercoils by SSB protein, which indicates a corresponding enhancement of the subunit mobilities in internal motions. Fluorescence polarization anisotropy measurements on free and complexed pBR322 DNA indicate a (predominantly) uniform torsional rigidity for the saturated DNA/SSB protein complex that is significantly reduced compared to the free DNA. These observations are all consistent with the notion that binding of SSB protein is accompanied by a gradual loss of supercoils and saturates when the superhelical twist is largely removed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
24
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4022-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Change of conformation and internal dynamics of supercoiled DNA upon binding of Escherichia coli single-strand binding protein.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't