Polymorphism of Amyloid Fibrils and their complexes with Catalase

Catalase binding to amyloid fibrils has been shown for the Alzheimer's amyloid-β (Aβ), type 2 diabetes-associated islet amyloid polypeptide (IAPP) and Creutzfeldt-Jakob disease-associated prion protein (PrP). Catalase targets a specific domain with a GAII-like sequence and there are a number of other amyloid fibril-forming proteins that contain related sequences, such as the Parkinson's associated α-synuclein protein and the Huntington disease protein Huntingtin. Using transmission electron microscopy (TEM) analysis, interactions show specific binding of catalase to some, but not all, fibrillar forms of Aβ, IAPP and PrP fragments, allowing determination of the fibrillar forms that contain an accessible GAII-like sequence. The catalase-amyloid interactions have been used to identify novel amyloid-binding compounds such as the kisspeptins and oligo(ethylene glycol) derivatives of 6-methylbenzothiazole aniline. The use of TEM and other imaging techniques to study amyloid-catalase interactions has the potential for discovery of new therapeutics for amyloid-associated disorders.