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Amyloid Assembly Endows Gad m 1 with Biomineralization Properties.

ABSTRACT: Acid proteins capable of nucleating Ca2+ and displaying aggregation capacity play key roles in the formation of calcium carbonate biominerals. The helix-loop helix EF-hands are the most common Ca2+-binding motifs in proteins. Calcium is bound by the loop region. These motifs are found in many proteins that are regulated by calcium. Gad m 1, an Atlantic cod ?-parvalbumin isoform, is a monomeric EF-hand protein that acts as a Ca2+ buffer in fish muscle; the neutral and acid apo-forms of this protein can form amyloids. Since Ca2+-nucleating proteins have a propensity to form extended ?-strand structures, we wondered whether amyloid assemblies of an EF-hand protein were able to influence calcium carbonate crystallization in vitro. Here, we used the Gad m 1 chain as a model to generate monomeric and amyloid assemblies and to analyze their effect on calcite formation in vitro. We found that only amyloid assemblies alter calcite morphology.

SUBMITTER: Castellanos M

PROVIDER: S-EPMC5871982 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Amyloid Assembly Endows Gad m 1 with Biomineralization Properties.

Castellanos Milagros M Torres-Pardo Almudena A Rodríguez-Pérez Rosa R Gasset María M

Biomolecules 20180320 1

Acid proteins capable of nucleating Ca2+ and displaying aggregation capacity play key roles in the formation of calcium carbonate biominerals. The helix-loop helix EF-hands are the most common Ca2+-binding motifs in proteins. Calcium is bound by the loop region. These motifs are found in many proteins that are regulated by calcium. Gad m 1, an Atlantic cod β-parvalbumin isoform, is a monomeric EF-hand protein that acts as a Ca2+ buffer in fish muscle; the neutral ...[more]

PMID: 29558422

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