Title: Elucidating Pathways of Insulin Fibrillation using Biophysical Methods

Graduate Student: Matthew T. Mawhinney

Abstract: Inducing human insulin into a brillar state via agitation and heating allows the investigation of the aggregation of proteins. Such methods as kinetic thioflavin T fluorescence and photo-induced cross-linking of unmodified proteins allows the pathway of insulin aggregation to be observed as a function of time, giving snapshots of the protein assembly along the way. It was observed that insulin brillation at neutral pH (7.3) only occurs when initially prepared low concentrations (< 50 µM); higher concentrations of insulin are able to form hexamers, stabilizing the protein and preventing any unfolding which may lead to nucleation, necessary for aggregation. In addition, the introduction of glucose and trehalose as crowding agents was found to inhibit insulin brillation with increasing concentration.

Advisor: Dr. Brigita Urbanc