Search results
Results from the WOW.Com Content Network
Amyloid beta (Aβ, Abeta or beta-amyloid) denotes peptides of 36–43 amino acids that are the main component of the amyloid plaques found in the brains of people with Alzheimer's disease. [2] The peptides derive from the amyloid-beta precursor protein (APP), which is cleaved by beta secretase and gamma secretase to yield Aβ in a cholesterol ...
Native-like amyloid fibrils in which native β-sheet containing proteins maintain their native-like structure in the fibrils have also been proposed. [50] There are few developed ideas on how the complex backbone topologies of disulfide-constrained proteins, which are prone to form amyloid fibrils (such as insulin and lysozyme), adopt the ...
Amyloid beta monomers are soluble and contain short regions of beta sheet and polyproline II helix secondary structures in solution, [5] though they are largely alpha helical in membranes; [6] however, at sufficiently high concentration, they undergo a dramatic conformational change to form a beta sheet-rich tertiary structure that aggregates ...
Amyloid beta (Aβ) is a small protein, most often 40 or 42 amino acids in length, that is released from a longer parent protein called the Aβ-precursor protein (APP). [24] APP is produced by many types of cell in the body, but it is especially abundant in neurons. It is a single-pass transmembrane protein, passing once through cellular ...
Beta sheets consist of beta strands (β-strands) connected laterally by at least two or three backbone hydrogen bonds, forming a generally twisted, pleated sheet. A β-strand is a stretch of polypeptide chain typically 3 to 10 amino acids long with backbone in an extended conformation .
Amyloid beta (Aβ) is composed of a family of peptides produced by proteolytic cleavage of the type I transmembrane spanning glycoprotein amyloid-beta precursor protein (APP). Amyloid plaque Aβ protein species ends in residue 40 or 42, [ 4 ] but it is suspected that Aβ42 form is crucial in the pathogenesis of AD.
Amyloid-forming proteins aggregate into distinctive fibrillar forms with a beta-sheet structure. [19] [20] The beta-sheet form of amyloid is proteolysis-resistant, meaning it can not be degraded or broken down. [5] As a result, amyloid deposits into the body's extracellular space. [5]
The alpha sheet has been proposed as a possible intermediate state in the conformational change in the formation of amyloid fibrils by peptides and proteins such as amyloid beta, poly-glutamine repeats, lysozyme, prion proteins, and transthyretin repeats, all of which are associated with protein misfolding disease.