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On the structural definition of amyloid fibrils and other polypeptide aggregates

Leibniz-Institut für Altersforschung, Beutenbergstrasse 11, 07745, Jena, Germany.
Cellular and Molecular Life Sciences CMLS (Impact Factor: 5.86). 09/2007; 64(16):2066-78. DOI: 10.1007/s00018-007-7110-2
Source: PubMed

ABSTRACT Amyloid fibrils occur inside the human body, associated with ageing or a group of diseases that includes, amongst others, Alzheimer's disease, atherosclerosis and type II diabetes. Many natural polypeptide chains are able to form amyloid fibrils in vivo or in vitro, and this ability has been suggested to represent an inherent consequence of the chemical structure of the polypeptide chain. Recent literature has provided a wealth of information about the structure of aggregates, precipitates, amyloid fibrils and other types of fibrillar polypeptide assemblies. However, the biophysical meaning associated with these terms can differ considerably depending on the context of their usage. This overview presents a structural comparison of amyloid fibrils and other types of polypeptide assemblies and defines amyloid fibrils, based on structural considerations, as fibrillar polypeptide aggregates with a cross-beta conformation.

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    • "Hence, the elucidation of individual structural polymorphs on an atomic level is challenging and the conclusions drawn so far are still controversial [26] [27] [28]. Obtaining structural constraints for models of full-length amyloid peptides and proteins beyond the molecular level proves to be a major task and requires considerable effort in designing suitable experimental protocols and the use of state-of-the-art instrumentation [9] [29] [30] [10] [11] [31]. "
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    Journal of Molecular Biology 01/2014; 426(2):362–376. DOI:10.1016/j.jmb.2013.10.020 · 4.33 Impact Factor
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    • "Where fibrils are comprised of β-sheets running perpendicular to the fibril axis, they are termed 'amyloid' or amyloid-like'. 'Amyloid' derives from the association with amyloidosis diseases, such as Alzheimer's and Parkinson's disease, and 'amyloid-like' refers to structurally similar fibrils formed in vitro (Fändrich, 2007). "
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