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Zinc modulates copper coordination mode in prion protein octa-repeat subdomains.

ABSTRACT: In this work we present and analyse XAS measurements carried out on various portions of Prion-protein tetra-octa-repeat peptides in complexes with Cu(II) ions, both in the presence and in the absence of Zn(II). Because of the ability of the XAS technique to provide detailed local structural information, we are able to demonstrate that Zn acts by directly interacting with the peptide, in this way competing with Cu for binding with histidine. This finding suggests that metal binding competition can be important in the more general context of metal homeostasis.

SUBMITTER: Stellato F

PROVIDER: S-EPMC4850921 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Zinc modulates copper coordination mode in prion protein octa-repeat subdomains.

Stellato Francesco F Spevacek Ann A Proux Olivier O Minicozzi Velia V Millhauser Glenn G Morante Silvia S

European biophysics journal : EBJ 20110628 11

In this work we present and analyse XAS measurements carried out on various portions of Prion-protein tetra-octa-repeat peptides in complexes with Cu(II) ions, both in the presence and in the absence of Zn(II). Because of the ability of the XAS technique to provide detailed local structural information, we are able to demonstrate that Zn acts by directly interacting with the peptide, in this way competing with Cu for binding with histidine. This finding suggests that metal binding competition ca ...[more]

PMID: 21710304

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