title: Sedimentation Velocity Analysis of the Size Distribution of Amyloid Oligomers and Fibrils.
abstract: Amyloid fibrils result from the self-assembly of proteins into large aggregates with fibrillar morphology and common structural features. These fibrils form the major component of amyloid plaques that are associated with a number of common and debilitating diseases, including Alzheimer's disease. While a range of unrelated proteins and peptides are known to form amyloid fibrils, a common feature is the formation of aggregates of various sizes, including mature fibrils of differing length and/or structural morphology, small oligomeric precursors, and other less well-understood forms such as amorphous aggregates. These various species can possess distinct biochemical, biophysical, and pathological properties. Sedimentation velocity analysis can characterize amyloid fibril formation in exceptional detail, providing a particularly useful method for resolving the complex heterogeneity present in amyloid systems. In this chapter, we describe analytical methods for accurate quantification of both total amyloid fibril formation and the formation of distinct amyloid structures based on differential sedimentation properties. We also detail modern analytical ultracentrifugation methods to determine the size distribution of amyloid aggregates. We illustrate examples of the use of these techniques to provide biophysical and structural information on amyloid systems that would otherwise be difficult to obtain.
authors.affiliation: Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia.
authors.forename: Yee-Foong
authors.initials: YF
authors.lastname: Mok
authors.affiliation: Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia. Electronic address: ghowlett@unimelb.edu.au.
authors.forename: Geoffrey J
authors.initials: GJ
authors.lastname: Howlett
authors.affiliation: Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia. Electronic address: mgriffin@unimelb.edu.au.
authors.forename: Michael D W
authors.initials: MD
authors.lastname: Griffin
mesh_terms: D000682:Amyloid / Q000737:chemistry / Q000302:isolation & purification* / Q000648:ultrastructure; D053304:Apolipoprotein C-II / Q000737:chemistry / Q000302:isolation & purification / Q000648:ultrastructure; D006801:Humans; D000071058:Huntingtin Protein; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000648:ultrastructure; D010316:Particle Size; D017510:Protein Folding; D020836:Protein Structure, Quaternary; D014461:Ultracentrifugation
chemical_list: D000682:Amyloid; D053304:Apolipoprotein C-II; C086055:HTT protein, human; D000071058:Huntingtin Protein; D009419:Nerve Tissue Proteins
keywords: Amyloid; Amyloid oligomer; Fibril size; Protein misfolding; Size distribution; Worm-like chain