RATIONALE Amyloid formation is implicated in a number of human diseases. β(2)-Microglobulin (β(2)m) is the precursor protein in dialysis-related amyloidosis and it has been shown that partial, or more complete, unfolding is key to amyloid fibril formation in this pathology. Here the relationship between conformational flexibility and β(2)m amyloid formation at physiological pH has been investig...

Recent advances in nanotechnologies have led to wide use of nanomaterials in biomedical field. However, nanoparticles are found to interfere with protein misfolding and aggregation associated with many human diseases. It is still a controversial issue whether nanoparticles inhibit or promote protein aggregation. In this study, we used molecular dynamics simulations to explore the effects of thr...

Alzheimer's disease (AD) is the most common form of dementia and associated with the progressive accumulation of amyloid β-peptides (Aβ) in form of extracellular amyloid plaques in the human brain. A critical role of Aβ in the pathogenesis of AD is strongly supported by gene mutations that cause early-onset familial forms of the disease. Such mutations have been identified in the APP gene itsel...

Amyloid-β and α-synuclein are intrinsically disordered proteins (IDPs), which are at the center of Alzheimer's and Parkinson's disease pathologies, respectively. These IDPs are extremely flexible and do not adopt stable structures. Furthermore, both amyloid-β and α-synuclein can form toxic oligomers, amyloid fibrils and other type of aggregates in Alzheimer's and Parkinson's diseases. Experimen...

protein aggregation and precipitation is associated with many debilitating diseases including alzheimer's, parkinson's, and light-chain amyloidosis. β-casein, a member of the casein family, has been demonstrated to exhibit chaperone-like activity to protect protein form aggregation. hofmeister salts (lyotropice series) are a class of ions which have an effect on the solubility and also the stab...

The inverse sequences of naturally occurring proteins display different folding and structural properties fail to retain the functions native despite identical fundamental features, such as amino acid composition, hydrophobicity, etc. To gain insight into physical mechanisms underlying secondary structure formation aggregation direct retro amyloidogenic peptides, we probed fibrillogenesis accom...

Protein misfolding and concomitant aggregation towards amyloid formation is the underlying biochemical commonality among a wide range of human pathologies. Amyloid formation involves the conversion of proteins from their native monomeric states (intrinsically disordered or globular) to well-organized, fibrillar aggregates in a nucleation-dependent manner. Understanding the mechanism of aggregat...

Aggregation at the neuronal cell membrane's lipid bilayer surface is implicated in amyloid-β (Aβ) toxicity associated with Alzheimer's disease; however, structural and mechanistic insights into the process remain scarce. We have identified a conserved binding mode of Aβ40 on lipid bilayer surfaces with a conserved helix containing the self-recognition site (K16-E22).

Mutations in the presenilins that cause familial Alzheimer's disease alter the activity of these proteases to increase generation of an aggregation-prone isoform of the amyloid β-peptide (Aβ). How these mutations do so has been unclear. Sannerud et al. now show that regulation of subcellular localization plays a central role, advancing our understanding of the cell biology of Alzheimer's disease.

Alzheimer's disease (AD) is marked by the accumulation of neuronal plaques from insoluble amyloid-beta (Aβ) peptides. Growing evidence for the role of Aβ oligomers in neuronal cell cytotoxicity and pathogenesis has prompted the development of novel techniques to better understand the early stages of aggregation. Near infrared (NIR) optical trapping was applied to characterize the early stages o...