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Stepwise dynamics of epitaxially growing single amyloid fibrils.

ABSTRACT: The assembly mechanisms of amyloid fibrils, tissue deposits in a variety of degenerative diseases, is poorly understood. With a simply modified application of the atomic force microscope, we monitored the growth, on mica surface, of individual fibrils of the amyloid beta25-35 peptide with near-subunit spatial and subsecond temporal resolution. Fibril assembly was polarized and discontinuous. Bursts of rapid (up to 300-nm(-1)) growth phases that extended the fibril by approximately 7 nm or its integer multiples were interrupted with pauses. Stepwise dynamics were also observed for amyloid beta1-42 fibrils growing on graphite, suggesting that the discontinuous assembly mechanisms may be a general feature of epitaxial amyloid growth. Amyloid assembly may thus involve fluctuation between a fast-growing and a blocked state in which the fibril is kinetically trapped because of intrinsic structural features. The used scanning-force kymography method may be adapted to analyze the assembly dynamics of a wide range of linear biopolymers.

SUBMITTER: Kellermayer MS

PROVIDER: S-EPMC2224175 | biostudies-literature | 2008 Jan

REPOSITORIES: biostudies-literature

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Stepwise dynamics of epitaxially growing single amyloid fibrils.

Kellermayer Miklós S Z MS Karsai Arpád A Benke Margit M Soós Katalin K Penke Botond B

Proceedings of the National Academy of Sciences of the United States of America 20071227 1

The assembly mechanisms of amyloid fibrils, tissue deposits in a variety of degenerative diseases, is poorly understood. With a simply modified application of the atomic force microscope, we monitored the growth, on mica surface, of individual fibrils of the amyloid beta25-35 peptide with near-subunit spatial and subsecond temporal resolution. Fibril assembly was polarized and discontinuous. Bursts of rapid (up to 300-nm(-1)) growth phases that extended the fibril by approximately 7 nm or its in ...[more]

PMID: 18162558

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Dataset Information

Stepwise dynamics of epitaxially growing single amyloid fibrils.

Publications

Stepwise dynamics of epitaxially growing single amyloid fibrils.

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