Amyloid fibril structures

Shiv]i A P, Brown F, Davies M C, Jennings K H, Roberts C J, Tendler S J B, Wilkinson M J and Williams P M 1995 Scanning tunnelling microscopy studies of p-amyloid fibril structure and assembly FEBS Lett. 371 25-8... 

Wang, J., Gulich, S., Bradford, C., Ramirez-Alvarado, M., and Regan, L. (2005). A twisted four-sheeted model for an amyloid fibril. Structure 13, 1279-1288. 

In view of the consideration that /(-solenoids and /(-arcades may also be structural elements of amyloid fibrils (Kajava et al., 2004 Lazo and Downing, 1998 Margittai and Langen, 2004 Pickersgill, 2003), sequence-based detection and structure prediction of /(-solenoid proteins are pertinent to the identification of amyloidogenic sequences and the elucidation of amyloid fibril structures. As with /(-solenoid domains, amyloidogenic regions of... 

Wetzel, R. (2002). Ideas of order for amyloid fibril structure. Structure 10, 1031. 

Tuite, M. F. (2000). Yeast prions and their prion-forming domain. Cell 100, 289-292. Tycko, R. (2000). Solid-state NMR as a probe of amyloid fibril structure. Curr. Opin. Chem. Biol. 4, 500-506. 

Serpell, L. C. (2000). Alzheimer s amyloid fibrils Structure and assembly. Biochim. Biophys. Acta 1502, 16-30. 

The notion of a common core structure has been further supported by synchrotron X-ray fiber diffraction patterns of several amyloid fibrils the patterns show common reflections in addition to those at 4.7 and 10 A (Sunde et al., 1997). Although these data give some insight into the arrangement of the amyloid fibril core, the exact molecular structure and organization of the proteins making up this common core have yet to be uniquely defined. The inherently noncrystalline, insoluble nature of the fibrils makes their structures difficult to study via traditional techniques of X-ray crystallography and solution NMR. An impressive breadth of biochemical and biophysical techniques has therefore been employed to illuminate additional features of amyloid fibril structure. 

The resultant data have led to the proposal of numerous molecular models of amyloid fibril structure (Makin and Serpell, 2005). These models can be separated into three general classes (Fig. 2) (1) the Refolding models,... 

Hiramatsu H, Kitagawa T. FT-IR approaches on amyloid fibril structure. Biochim. Biophys. Acta 2005 1753 100. 

R. Tycko, Solid-State NMR as a Probe of Amyloid Fibril Structure ,... 

Levine III, H. (1999) Quantification of beta-sheet amyloid fibril structures with thioflavin T. Methods Enzymol, 309, 274-84. 

Tycko R (2011) Solid-state NMR studies of amyloid fibril structure. Annu Rev Phys Chem 62 279-299... 

Serpell LC (2000) Alzheimer s amyloid fibrils structure and assembly. Biochim Biophys Acta 1502 16-30 Serpell LC, Fraser PE, Sunde M (1999) X-ray fiber diffraction of amyloid fibrils. Methods Enzymol 309 526-536... 

Wetzel R (2002) Ideas of order for amyloid fibril structure. Structure (Camb) 10 1031-1036 Wigley WC, Corboy Ml, Cutler TD, Thibodeau PH, Oldan J, Lee MG, Rizo J, Hunt JF, Thomas PJ (2002) A protein sequence that can encode native structure by disfavoring alternate conformations. Nat Stmct Biol 9 381-388... 

Because the mechanical properties of amyloid fibrils are derived from AFM nanoindentation measurements on the basis of assumptions about the geometry of the fibrils, they cannot provide highly accurate information about deformation. Because of the vague information on structures, to determine how different loading conditions affect the amyloid fibrils structures and mechanical properties, we must resort to simulation. Thanks to the development of the molecular dynamics approach, one can obtain the Young s modulus of a biological system... 

Hirohata M, Hasegawa K, Tsutsumi-Yasuhara S, Ohhashi Y, Ookoshi T, Ono K, Yamada M, Naiki H (2007) The anti-amyloidogenic effect is exerted against Alzheimer s beta-amyloid fibrils in vitro by preferential and reversible binding of flavonoids to the amyloid fibril structure. Biochemistry 46(7) 1888-1899. doi 10.1021/bi061540x... 

Finally, paramagnetic relaxation was used in order to determine the effects of metal ion association with amyloid fibrils. Several specific sites of Cu were detected in the amyloid protein AjS(l O) using PRE and shift perturbation data firom solid-state NMR, and corroborated using detailed molecular dynamics (MD) models. It was also found by this means that the amyloid fibril structure is not significantly altered by Cu binding. This smdy is particularly interesting on account of its medical pertinence, as Cu° is often found at elevated concentration in cells containing Alzheimers plaques [103]. 

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