Amyloid fibrils are β-sheet-rich protein aggregates commonly found in the organs and tissues of patients with various amyloid-associated diseases. Understanding the structural organization of amyloid fibrils can be beneficial for the search of drugs to successfully treat diseases associated with protein misfolding. The structure of insulin fibrils was characterized by deep ultraviolet resonance...

The folding of a protein from a sequence of amino acids to a well-defined tertiary structure is one of the most studied and enigmatic events to take place in biological systems. Relatively recently, it has been established that some proteins and peptides are able to take on conformations other than their native fold to form long fibres known as amyloid. In vivo, these are associated with misfol...

Amyloid fibrils are associated with a number of different neurodegenerative diseases. Detailed knowledge the fibril structure will be importance in search therapy and may guide experiments to understand amyloid formation. In this paper we investigate morphology α -synuclein fibrils, Parkinson’s disease, formed under conditions. particular, study, by means small wide-angle X-ray scattering, whet...

Congo red (CR) binding, monitored by characteristic yellow-green birefringence under crossed polarization has been used as a diagnostic test for the presence of amyloid in tissue sections for several decades. This assay is also widely used for the characterization of in vitro amyloid fibrils. In order to probe the structural specificity of Congo red binding to amyloid fibrils we have used an in...

PURPOSE Mature-onset cataract results from the formation of light-scattering aggregates of lens crystallins. Although oxidative or mutational damage may be a prerequisite, little is known of the initiation or nucleation of these aggregated states. In mice carrying mutations in gamma-crystallin genes, a truncated form of gamma-crystallin formed intranuclear filamentous inclusions within lens fib...

Prealbumin from an individual with heredofamilial amyloid polyneuropathy of Swedish origin was isolated from plasma by using a three-step procedure involving ion exchange, Affi-gel Blue affinity chromatography, and gel filtration. This prealbumin and its associated amyloid fibril subunit protein were digested with trypsin and the resulting peptides were separated by high performance liquid chro...

Amyloid fibrils are ordered beta-sheet aggregates of proteins that are associated with over twenty human diseases. Several are neurodegenerative disorders which include Alzheimer’s and Parkinson’s disease. Interestingly, it has been postulated that all proteins can be induced to form this low energy state if subjected to the right conditions. Presently there is no cure for amyloid related disea...

This mini-review focuses on the processes and consequences of protein folding and misfolding. The latter process often leads to protein aggregation and precipitation with the aggregates adopting either highly ordered (amyloid fibril) or disordered (amorphous) forms. In particular, the amyloid fibril is discussed because this form has gained considerable notoriety due to its close links to a var...

We consider nucleation of amyloid fibrils in the case when the process occurs by the mechanism of direct polymerization of practically fully extended protein segments, i.e., beta-strands, into beta-sheets. Applying the classical nucleation theory, we derive a general expression for the work to form a nanosized amyloid fibril (protofilament) constituted of successively layered beta-sheets. Analy...

Most of the disease causing proteins such as beta amyloid, amylin, and huntingtin protein, which are natively disordered, readily form fibrils consisting of beta-sheet polymers. Though all amyloid fibrils are made up of beta-sheet polymers, not all peptides with predominant beta-sheet content in the native state develop into amyloid fibrils. We hypothesize that stable amyloid like fibril format...