The α‐sheet: A missing‐in‐action secondary structure?

The α‐sheet has been speculated to play a role as a toxic conformer in amyloid diseases. However, except for relatively short fragments, its detection has remained elusive. Here, we present molecular dynamics simulations that support the existence of the α‐sheet as a stable, metastable, or long‐lived secondary structure in polyglutamine and, to a lesser extent, in polyasparagine aggregates. Proteins 2011. © 2010 Wiley‐Liss, Inc.

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