Modulation of Aβ_1-42 Aggregation by a SARS-CoV-2 Protein Fragment

A number of studies have pointed out the possibility that SARS-CoV-2 infections could trigger amyloid diseases such as Parkinson's disease or type II diabetes. In the present study, we probe this question for Alzheimer's disease, which is connected with the presence of amyloids rich in Aβ peptides. For this purpose, we study, by way of molecular dynamics simulations, the interaction between the fragment FKNIDGYFKI of the Spike protein with an Aβ_1-42 monomer and two fibril models, one patient-derived and one synthetic. We find that the viral protein fragment appears to shift the ensemble of monomer conformations toward more aggregation-prone ones, and that fibril polymorphs found in patients with Alzheimer's disease appear to be more stabilized than synthetic fibrils. We discuss commonalities and differences in the modulation of amyloid formation by the viral protein fragments by comparing our results with previous studies of other amyloid-forming proteins.