We have developed a highly coarse grained model
to study the aggregation of α-synuclein.
We model a protein as a chain of twelve particles that can change their
internal states, and therby shape and interaction parameters,
in response to the environment.
A protein in the disordered state is modelled as a random chain of soft spheres.
By transformations of some of the particles into spherocylinders and by rearrangement into
a planar configuration, the protein can adopt an ordered state capable of forming fibrils.
In a first representation we coarse grained a protein into a single
polymorph patchy-particle, that can change conformation
depending on the environment.
Simulation results show the formation of oligomers and fibrils by a direct nucleation-and-growth
mechanism, by two-step-nucleation through the conversion of an oligomer
into a fiber or vice versa, and by fibril-enhanced conversion
of oligomers into fibrils.