Figure 2.

Point mutations in Aβ alter the temporal appearance of distinct aggregate forms. AFM images demonstrate the aggregation of Wild Type, Arctic, Italian, Iowa, or Flemish Aβ(1–40). Incubations with protein concentration of 20 μM were imaged at different time points after the dilution of DMSO stocks into PBS buffer. Examples of oligomers, the larger subpopulation oligomers, protofibrils, and fibrils are indicated by black, magenta, blue, and green arrows, respectively. At 1 h, Wild Type and mutant Aβ peptides all formed predominately oligomeric aggregates. However, heterogeneous mixtures of aggregate types appeared at later times for all incubations.