All amyloid comprises fibrillar polymers of tightly associated protein monomers. Central to the fibril structure is a highly ordered β-pleated sheet domain although this interacting region may only be a relatively short stretch of each constituent polypeptide chain. Fibril formation begins as a nucleation event based either on the constituent monomer protein or its proteolytic fragment(s). The resulting fibrils are generally chemically inert and very stable.
Part of the book: Amyloid Diseases