Single Point Mutation from E22-to-K in Aβ Initiates Early-Onset Alzheimer’s Disease by Binding with Catalase

Figure 4

E22K induced stronger self-aggregation than Aβ in vitro. (a) The 21–23 residues in the α-helix structure of Aβ (PDB ID: 1IYT). (b) The theoretical simulated 3D crystal structure of H₂O₂ (red) binding with the E22 (blue) and D23 (purple) residues of Aβ (green). (c) The theoretical simulated 3D crystal structure of H₂O₂ (red) binding with the K22 (blue) residue of E22K (green). (d) The effects of a single mutation in K16P, F19P, E22P, and D23P, respectively, and a double mutation, E22D23P, on β-sheet formation as detected by Th T dye. (e–h) The effects of H₂O₂ and L-cys on β-sheet and fibril formation at 0 and 24 h as detected by Th T dye and TEM. Bar: 0.2 μm. Experiments were repeated in triplicate. . Data are .

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