Figure S3.

Analysis of the Stability of the Different Protein Species against Proteinase K Degradation, Related to Figure 3

(A) Incubations of an aliquot of an aggregation sample at late incubation times (around 100 h) with different concentrations of proteinase K were analyzed by single-molecule fluorescence to determine the stability of the different oligomeric species against proteinase K degradation. The pair of A_small and A_med distributions shows similar dependence on proteinase K concentration, as well as for the pair of B_med and B_large distributions, although this latter pair has much higher resistance to proteinase K.

(B) The stability to proteinase K degradation of monomeric and fibrillar forms of αS was estimated from the disappearance of the band corresponding to full-length monomeric in a SDS-PAGE gel. Different concentrations of proteinase K were used as indicated in the figure. All samples from monomeric, fibrillar and oligomeric forms of αS were treated exactly in the same way for direct comparison.