The elevated copper binding strength of amyloid-β aggregates allows the sequestration of copper from albumin: a pathway to accumulation of copper in senile plaques.

Copper coexists with amyloid-β (Aβ) peptides at a high concentration in the senile plaques of Alzheimer's disease (AD) patients and has been linked to oxidative damage associated with AD pathology. However, the origin of copper and the driving force behind its accumulation are unknown. We designed a sensitive fluorescent probe, Aβ(1-16)(Y10W), by substituting the tyrosine residue at position 10 in the hydrophilic domain of Aβ(1-42) with tryptophan.

Ternary complexes of iron, amyloid-beta, and nitrilotriacetic acid: binding affinities, redox properties, and relevance to iron-induced oxidative stress in Alzheimer's disease.

The interaction of amyloid-beta (Abeta) and redox-active metals, two important biomarkers present in the senile plaques of Alzheimer's disease (AD) brain, has been suggested to enhance the Abeta aggregation or facilitate the generation of reactive oxygen species (ROS). This study investigates the nature of the interaction between the metal-binding domain of Abeta, viz., Abeta(1-16), and the Fe(III) or Fe(II) complex with nitrilotriacetic acid (NTA).

Mechanistic studies of Cu(II) binding to amyloid-beta peptides and the fluorescence and redox behaviors of the resulting complexes.

Due in large part to the lack of crystal structures of the amyloid-beta (Abeta) peptide and its complexes with Cu(II), Fe(II), and Zn(II), characterization of the metal-Abeta complex has been difficult. In this work, we investigated the complexation of Cu(II) by Abeta through tandem use of fluorescence and electron paramagnetic resonance (EPR) spectroscopies. EPR experiments indicate that Cu(II) bound to Abeta can be reduced to Cu(I) using sodium borohydride and that both Abeta-Cu(II) and Abeta-Cu(I) are chemically stable.