Conversion between parallel and antiparallel ?-sheets in wild-type and Iowa mutant A?40 fibrils.
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ABSTRACT:
SUBMITTER: Xi W
PROVIDER: S-EPMC5785298 | biostudies-literature | 2018 Jan
REPOSITORIES: biostudies-literature
Publications
Conversion between parallel and antiparallel β-sheets in wild-type and Iowa mutant Aβ<sub>40</sub> fibrils.
Xi Wenhui W Hansmann Ulrich H E UHE
The Journal of chemical physics 20180101 4
Using a variant of Hamilton-replica-exchange, we study for wild type and Iowa mutant Aβ<sub>40</sub> the conversion between fibrils with antiparallel β-sheets and such with parallel β-sheets. We show that wild type and mutant form distinct salt bridges that in turn stabilize different fibril organizations. The conversion between the two fibril forms leads to the release of small aggregates that in the Iowa mutant may shift the equilibrium from fibrils to more toxic oligomers. ...[more]
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