The Mechanism of Amyloid Spherulite Formation by Bovine Insulin

ABSTRACT

The formation of amyloid-containing spherulite-like structures has been observed in some instances of amyloid diseases, as well as in amyloid fibril-containing solutions in vitro. In this article we describe the structure and kinetics of bovine insulin amyloid fibril spherulites formed in the presence and absence of different salts and at different salt concentrations. The general spherulite structure consists of radially oriented amyloid fibrils, as shown by optical microscopy and environmental scanning electron microscopy. In the center of each spherulite, a "core" of less regularly oriented material is observed, whose size decreases when the spherulites are formed in …