title: Structure of the cross-beta spine of amyloid-like fibrils.
abstract: Numerous soluble proteins convert to insoluble amyloid-like fibrils that have common properties. Amyloid fibrils are associated with fatal diseases such as Alzheimer's, and amyloid-like fibrils can be formed in vitro. For the yeast protein Sup35, conversion to amyloid-like fibrils is associated with a transmissible infection akin to that caused by mammalian prions. A seven-residue peptide segment from Sup35 forms amyloid-like fibrils and closely related microcrystals, from which we have determined the atomic structure of the cross-beta spine. It is a double beta-sheet, with each sheet formed from parallel segments stacked in register. Side chains protruding from the two sheets form a dry, tightly self-complementing steric zipper, bonding the sheets. Within each sheet, every segment is bound to its two neighbouring segments through stacks of both backbone and side-chain hydrogen bonds. The structure illuminates the stability of amyloid fibrils, their self-seeding characteristic and their tendency to form polymorphic structures.
authors.affiliation: Howard Hughes Medical Institute, UCLA-DOE Institute for Genomics and Proteomics, Box 951570, UCLA, Los Angeles, California 90095-1570, USA.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Nelson
authors.forename: Michael R
authors.initials: MR
authors.lastname: Sawaya
authors.forename: Melinda
authors.initials: M
authors.lastname: Balbirnie
authors.forename: Anders Ø
authors.initials: AØ
authors.lastname: Madsen
authors.forename: Christian
authors.initials: C
authors.lastname: Riekel
authors.forename: Robert
authors.initials: R
authors.lastname: Grothe
authors.forename: David
authors.initials: D
authors.lastname: Eisenberg
mesh_terms: D000577:Amides / Q000737:chemistry; D000595:Amino Acid Sequence; D000682:Amyloid / Q000737:chemistry* / Q000378:metabolism; D003460:Crystallization; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism; D010454:Peptide Termination Factors; D011328:Prions / Q000737:chemistry* / Q000378:metabolism; D017433:Protein Structure, Secondary; D012441:Saccharomyces cerevisiae / Q000737:chemistry*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000378:metabolism; D013816:Thermodynamics
chemical_list: D000577:Amides; D000682:Amyloid; D010446:Peptide Fragments; D010454:Peptide Termination Factors; D011328:Prions; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins