Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1999-2-16
pubmed:abstractText
C-reactive protein (CRP) is a pentameric oligoprotein composed of identical 23 kD subunits which can be modified by urea-chelation treatment to a form resembling the free subunit termed modified CRP (mCRP). mCRP has distinct physicochemical, antigenic, and biologic activities compared to CRP. The conditions under which CRP is converted to mCRP, and the molecular forms in the transition, are important to better understand the distinct properties of mCRP and to determine if the subunit form can convert back to the pentameric native CRP form. This study characterized the antigenic and conformational changes associated with the interconversion of CRP and mCRP. The rate of dissociation of CRP protomers into individual subunits by treatment in 8 M urea-10 mM EDTA solution was rapid and complete in 2 min as assayed by an enzyme-linked immunofiltration assay using monoclonal antibodies specific to the mCRP. Attempts to reconstitute pentameric CRP from mCRP under renaturation conditions were unsuccessful, resulting in a protein retaining exclusively mCRP characteristics. Using two-dimensional urea gradient gel electrophoresis, partial rapid unfolding of the pentamer occurred above 3 M urea, a subunit dissociation at 6 M urea, and further subunit unfolding at 6-8 M urea concentrations. The urea gradient electrophoresis results suggest that there are only two predominant conformational states occurring at each urea transition concentration. Using the same urea gradient electrophoresis conditions mCRP migrated as a single molecular form at all urea concentrations showing no evidence for reassociation to pentameric CRP or other aggregate form. The results of this study show a molecular conversion for an oligomeric protein (CRP) to monomeric subunits (mCRP) having rapid forward transition kinetics in 8 M urea plus chelator with negligible reversibility.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1357-2725
pubmed:author
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1415-26
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Conversion of native oligomeric to a modified monomeric form of human C-reactive protein.
pubmed:affiliation
Department of Cell and Molecular Biology, Northwestern University Medical School, Chicago, IL 60611, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't