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The oligomeric structures of aggregating proteins,the mechanism of their formation,the inhibition and disaggregation of these oligomers have been considered as an ongoing experimental and computational challenge to therapy neurodegenerative diseases.The hydrophobic fragments are a general key segment in these aggregation,such as GVIGIAQ in SOD1 and KLVFFAE in Aβ.The previous experiments and simulations showed fullerene C60 can inhibit the formation of KLVFFAE fibril,resulting from the strong hydrophobic and aromatic-stacking interactions between fullerene hexagonal rings and Phe rings.Yet the aggregation of yeast prion protein Sup35 due to its hydrophilic heptapeptide,GNNQQNY.The molecular mechanism of its aggregation and the effect of hydrophobic nanoparticles on such aggregating hydrophilic peptides become attractive too.To get more insight into the aggregation of the hydrophilic peptides,here we use replica exchange molecular dynamics simulations to address the characteristics of GNNQQNY aggregation and the effect of fullerene on its aggregation at neutral environment.Our simulations reveal that GNNQQNY octamers form various β-sheet rich structures,including β-sheet bilayer and β-barrels,via many hydrogen bonds of main chains and side chains and the complementary conformation of side-chain groups.Fullerenes mainly interact with glutamine and damage mutual coordination,hydrogen bonds among residues so that these toxic ordered structures of the oligomer are decrease.This phenomenon illustrates that fullerene can significantly inhibit the self-assembly of hydrophilic peptides.