期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2004
卷号:101
期号:13
页码:4435-4440
DOI:10.1073/pnas.0306786101
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Protein deposition as amyloid fibrils underlies many debilitating human disorders. The complexity and size of disease-related polypeptides, however, often hinders a detailed rational approach to study effects that contribute to the process of amyloid formation. We report here a simplified peptide sequence successfully designed de novo to fold into a coiled-coil conformation under ambient conditions but to transform into amyloid fibrils at elevated temperatures. We have determined the crystal structure of the coiled-coil form and propose a detailed molecular model for the peptide in its fibrillar state. The relative stabilities of the two structural forms and the kinetics of their interconversion were found to be highly sensitive to small sequence changes. The results reveal the importance of specific packing interactions on the kinetics of amyloid formation and show the potential of this exceptionally favorable system for probing details of the molecular origins of amyloid disease.