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Modulating amyloid self-assembly and fibril morphology with Zn(II).

ABSTRACT: Metal ions (Zn(II)) are demonstrated as probes of amyloid structure in simple segments of the Abeta peptide, Abeta(13-21). By restricting the possible metal binding sites to His13/His14 dyad, we show that Zn2+ can specifically control the rate of self-assembly and dramatically regulate amyloid morphology via distinct coordination environments as characterized by X-ray absorption spectroscopy. The data establish that the single His13 is sufficient to coordinate Zn2+ productively for typical amyloid fiber formation, while a distinct Zn2+ coordination environment can be accessed in the presence of His13/Hi14 dyad to stabilize sheet/sheet associations and the transition to a ribbon/tube morphology.

SUBMITTER: Dong J

PROVIDER: S-EPMC3555692 | biostudies-literature | 2006 Mar

REPOSITORIES: biostudies-literature

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Modulating amyloid self-assembly and fibril morphology with Zn(II).

Dong Jijun J Shokes Jacob E JE Scott Robert A RA Lynn David G DG

Journal of the American Chemical Society 20060301 11

Metal ions (Zn(II)) are demonstrated as probes of amyloid structure in simple segments of the Abeta peptide, Abeta(13-21). By restricting the possible metal binding sites to His13/His14 dyad, we show that Zn2+ can specifically control the rate of self-assembly and dramatically regulate amyloid morphology via distinct coordination environments as characterized by X-ray absorption spectroscopy. The data establish that the single His13 is sufficient to coordinate Zn2+ productively for typical amylo ...[more]

PMID: 16536526

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