Linked Life Data

11467958

Source:http://linkedlifedata.com/resource/pubmed/id/11467958

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
30
pubmed:dateCreated
2001-7-24
pubmed:abstractText
A wide variety of viruses require the transient presence of scaffolding proteins to direct capsid assembly. In the case of bacteriophage P22, a model in which the scaffolding protein selectively stabilizes on-pathway growing intermediates has been proposed. The stoichiometry and thermodynamics of binding of the bacteriophage P22 scaffolding protein within the procapsid were analyzed by light scattering and isothermal titration calorimetry. Calorimetric experiments carried out between 10 and 37 degrees C were consistent with the presence of at least two distinct populations of binding sites, in agreement with kinetic evidence obtained by a light scattering assay. Binding to the high-affinity sites occurred at 20 degrees C with a stoichiometry of approximately 60 scaffolding molecules per procapsid and an apparent K(d) of approximately 100-300 nM and was almost completely enthalpy-driven. For the second binding population, precise fitting of the data was impossible due to small heats of binding, but the thermodynamics of binding were clearly distinct from the high-affinity phase. The heat capacity change (DeltaC(p)()) of binding was large for the high-affinity sites and negative for both sets of sites. Addition of sodium chloride (1 M) greatly reduced the magnitude of the apparent DeltaH, in agreement with previous evidence that electrostatic interactions play a major role in binding. A mutant scaffolding protein that forms covalent dimers (R74C/L177I) bound only to the high-affinity sites. These data comprise the first quantitative measurements of the energetics of the coat protein/scaffolding protein interaction.
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
31
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8962-70
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Kinetic and calorimetric evidence for two distinct scaffolding protein binding populations within the bacteriophage P22 procapsid.
pubmed:affiliation
Laboratory for Biological Calorimetry, Biomolecular Analysis Group, Center for Biophysical Science and Engineering, and Department of Microbiology, University of Alabama at Birmingham, 35294, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.