Figure 1.
Schematic diagram of the effects of carbon NPs on the oligomerizations of initial disordered IAPP22–28 peptides: (A) for four peptides; (B) for eight peptides.
Peptides are shown as cartoon, with β-sheet in yellow, β-bridge in lime, and others in white. The NPs are shown as sticks in ice blue. In the two sets, a presents the initial structure of 4-/8-peptide system without NP, and b presents their conformations after 200 ns simulations. In addition, c, d, and e present the corresponding conformations of the peptides interacting with graphene, SWCNT, or C60 after 200 ns simulations, respectively.
Figure 2.
Secondary structure profile for four IAPP22–28 peptides in the absence or presence of carbon NPs.
The four peptides are labeled from C1 to C4, respectively.
Figure 3.
Secondary structure profile for eight IAPP22–28 peptides in the absence or presence of carbon NPs.
The eight peptides are labeled from C1 to C8, respectively.
Figure 4.
Time series of β-sheet contents for IAPP22–28 peptides in the absence or presence of NPs.
Figure 5.
The distribution of different β-sheet size for IAPP22–28 peptides with or without C60.
Figure 6.
The number of backbone hydrogen bonds and structural evolution: a) four peptides without NPs; b) eight peptides without NPs.
Peptides are shown as cartoon: β-sheet in yellow, and others in white.
Figure 7.
Contact numbers between peptides and nanoparticles over the whole simulation time.
For clarity, a windowed average is shown as a solid green line for each system.
Figure 8.
Probability distribution of the minimum distance between the side chain of each residue and the NP surface.
Only the last 50 ns simulations are considered.
Figure 9.
Detailed information of π–π stacking interaction between F23 residues and NPs: a). Representative structure of graphene interacting with 4 IAPP22–28 peptides; b) Representative structure of graphene interacting with 8 IAPP22–28 peptides; c) Probability distribution of the average distance between heavy atoms of F23 side chain and NPs.
The heavy atoms of F23 side chain are shown as sticks, and peptides are shown as cartoon.
Table 1.
Contents of different β-sheet sizes for 4 or 8 peptides with or without C60 in the last 50 ns simulations.
Figure 10.
Contact map between the side chains of hydrophobic residues in different chains for each system.
Only the last 50 ns trajectories are considered.