FIGURE 4.

Recombinant MspA monomers are extremely amyloidogenic and form amyloids in vitro under a wide range of conditions. A, SDS-PAGE of purified recombinant MspA protein. The gel was overloaded to visualize impurities. These accounted for <5% of the total proteins. The numbers to the left indicate the molecular mass (kDa) of the marker proteins. B, fibrillation kinetics evaluated by stopped flow and ThT fluorescence at various pH values. C, transmission electron micrographs of MspA amyloids formed in vitro at various pH values with low (30 mm) and high (150 mm) ionic strength (IS). The scale bars represent 100 nm.