Soluble multimeric Alzheimer beta(1-40) pre-amyloid complexes in dilute solution.

H Levine

doi:10.1016/0197-4580(95)00052-g

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Soluble multimeric Alzheimer beta(1-40) pre-amyloid complexes in dilute solution.

H Levine

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Abstract

Aqueous solutions of beta(1-40) peptide spontaneously associate to form pentameric/hexameric complexes that can be demonstrated by SDS-PAGE following treatment with glutaraldehyde and borohydride reduction. Under amyloidogenic conditions of pH and high peptide concentration these aggregates can further associate to form pentameric/hexameric complexes that can be demonstrated by SDS-PAGE following treatment with glutaraldehyde and borohydride reduction. Under amyloidogenic conditions of pH and high peptide concentration these aggregates can further associate to form sedimentable and filterable structures with beta-sheet amyloid characteristics of Thioflavine T fluorescence. The presence of such preamyloid structures at low peptide concentration suggests a mechanism by which amyloid plaques can accrete additional material by a cooperative rather than monomeric growth. The existence of a monomer<==>multimer equilibrium may partly explain the divergence of biological consequences with respect to neurotoxicity.

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Amino Acid Sequence Amyloid beta-Peptides Amyloid beta-Protein Precursor Cross-Linking Reagents Glutaral Microscopy, Electron Molecular Sequence Data Peptide Fragments Polymers Solubility Solutions Journal Article

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H Levine. Soluble multimeric Alzheimer beta(1-40) pre-amyloid complexes in dilute solution.. https://doi.org/10.1016/0197-4580(95)00052-g

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