Relation between molecular shape and the morphology of self-assembling aggregates: a simulation study

Proteins can aggregate in a wide variety of structures, both compact and extended. We present simulations of a coarse-grained anisotropic model that reproduce many of the experimentally observed aggregate structures. Conversely, all structures predicted by our model have experimental counterparts (ribbons, multistranded fibrils, and vesicles). The model we use is that of a rodlike particle with an attractive (hydrophobic) stripe on its side. Our Monte Carlo simulations show that aggregate morphologies crucially depend on two parameters. The first one is the width of the attractive stripe and the second one is a presence or absence of attractive interactions at the particle ends. These results provide us with a generic insight into the relation between the shape of protein-protein interaction potential and the morphology of protein aggregates.