Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2000-9-12
pubmed:abstractText
Cu and Zn have been shown to accumulate in the brains of Alzheimer's disease patients. We have previously reported that Cu(2+) and Zn(2+) bind amyloid beta (Abeta), explaining their enrichment in plaque pathology. Here we detail the stoichiometries and binding affinities of multiple cooperative Cu(2+)-binding sites on synthetic Abeta1-40 and Abeta1-42. We have developed a ligand displacement technique (competitive metal capture analysis) that uses metal-chelator complexes to evaluate metal ion binding to Abeta, a notoriously self-aggregating peptide. This analysis indicated that there is a very-high-affinity Cu(2+)-binding site on Abeta1-42 (log K(app) = 17.2) that mediates peptide precipitation and that the tendency of this peptide to self-aggregate in aqueous solutions is due to the presence of trace Cu(2+) contamination (customarily approximately 0.1 microM). In contrast, Abeta1-40 has much lower affinity for Cu(2+) at this site (estimated log K(app) = 10.3), explaining why this peptide is less self-aggregating. The greater Cu(2+)-binding affinity of Abeta1-42 compared with Abeta1-40 is associated with significantly diminished negative cooperativity. The role of trace metal contamination in inducing Abeta precipitation was confirmed by the demonstration that Abeta peptide (10 microM) remained soluble for 5 days only in the presence of high-affinity Cu(2+)-selective chelators.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-3042
pubmed:author
pubmed:issnType
Print
pubmed:volume
75
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1219-33
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Characterization of copper interactions with alzheimer amyloid beta peptides: identification of an attomolar-affinity copper binding site on amyloid beta1-42.
pubmed:affiliation
Laboratory for Oxidation Biology, Massachusetts General Hospital and Harvard Medical School, Boston 02129-9142, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't