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Correlation of copper interaction, copper-driven aggregation, and copper-driven h(2)o(2) formation with a?40 conformation.

ABSTRACT: The neurotoxicity of A? is associated with the formation of free radical by interacting with redox active metals such as Cu(2+). However, the relationship between ion-interaction, ion-driven free radical formation, and A? conformation remains to be further elucidated. In the present study, we investigated the correlation of Cu(2+) interaction and Cu(2+)-driven free radical formation with A?40 conformation. The Cu(2+)-binding affinity for A?40 in random coiled form is 3-fold higher than that in stable helical form. Unexpectedly but interestingly, we demonstrate in the first time that the stable helical form of A?40 can induce the formation of H(2)O(2) by interacting with Cu(2+). On the other hand, the H(2)O(2) generation is repressed at A?/Cu(2+) molar ratio ?1 when A?40 adopts random coiled structure. Taken together, our result demonstrates that A?40 adopted a helical structure that may play a key factor for the formation of free radical with Cu(2+) ions.

SUBMITTER: Yang CA

PROVIDER: S-EPMC3018625 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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Correlation of copper interaction, copper-driven aggregation, and copper-driven h(2)o(2) formation with aβ40 conformation.

Yang Chia-Anne CA Chen Yung-Han YH Ke Shyue-Chu SC Chen Yi-Ru YR Huang Hsien-Bin HB Lin Ta-Hsien TH Chen Yi-Cheng YC

International journal of Alzheimer's disease 20101230

The neurotoxicity of Aβ is associated with the formation of free radical by interacting with redox active metals such as Cu(2+). However, the relationship between ion-interaction, ion-driven free radical formation, and Aβ conformation remains to be further elucidated. In the present study, we investigated the correlation of Cu(2+) interaction and Cu(2+)-driven free radical formation with Aβ40 conformation. The Cu(2+)-binding affinity for Aβ40 in random coiled form is 3-fold higher than that in s ...[more]

PMID: 21234305

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Dataset Information

Correlation of copper interaction, copper-driven aggregation, and copper-driven h(2)o(2) formation with a?40 conformation.

Publications

Correlation of copper interaction, copper-driven aggregation, and copper-driven h(2)o(2) formation with aβ40 conformation.

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