Structural Model of the Amyloid Fibril Formed by β2-Microglobulin #21-31 Fragment Based on Vibrational Spectroscopy.

The article reports that native structures of peptides in proteins have been thought to represent the most stable among the possible conformations that a peptide can take. However, amyloid fibrils are now considered to be stable structures for peptide aggregates. The relationship between the secondary structural preferences of individual residue native proteins and amyloid fibrils has not been fully addressed because only fibril structures of short peptides have been examined so far. The secondary structures of component residues in the peptide were deduced from the shifted amide I frequencies of peptides specifically labeled with on the carbonyl group of the main chain.