Steric Zippers Play Key Role In Amyloid Fibrils

Two years ago, David Eisenberg of the University of California, Los Angeles, and a collaborative international group obtained the first atomic structure of an amyloid fibril formed from a yeast prion protein and found that an interdigitated β-sheet structure called a steric zipper was essential to fibril formation (C&EN, June 13, 2005, page 9).

Now, the same group has confirmed that steric zippers are a common structural feature in such aggregates by determining the atomic structures of microcrystals formed by 30 peptides associated with Alzheimer's disease, Parkinson's disease, type 2 diabetes, Creutzfeldt-Jakob disease, and other amyloid-related conditions (Nature, DOI: 10.1038/nature05695).

The researchers used specialized techniques, including synchrotron radiation microcrystallography, to obtain structures of the amyloid microcrystals, which otherwise would be too small to permit structural analysis. The work suggests that "amyloid diseases are similar not only on the fibril level, but also on the molecular level," the researchers write.