Formation of mixed fibrils demonstrates the generic nature and potential utility of amyloid nanostructures

The aggregation of proteins and peptides in the form of stable and highly o rdered amyloid fibrils is most commonly associated with pathological condit ions such as Alzheimer's disease and the transmissible spongiform encephalo pathies. The involvement of only a handful of proteins in amyloid formation in vivo has commonly been thought of as the result of some unusual conform ational characteristic of the sequences of the proteins involved. Recent ev idence has however suggested that the formation of these highly ordered str uctures is a generic process arising from the fundamental physicochemical p roperties of the polypeptide chain. In this study, we have shown that we ca n incorporate short peptides into amyloid fibrils assembled from unrelated peptides and from a full-length protein. This result provides compelling ev idence that amyloid fibril assembly is a fundamental property of polypeptid e chains. We have also demonstrated by doping with fluorescently labeled pe ptides that the fibrils can be modified to incorporate unusual functional g roups, suggesting the possibility of the production of a wide range of nove l nanomaterials with potentially important properties.