Ultrastructure of α-synuclein fibrils formed in
pure water
and 10 mM MES/NaOH, pH 5.5. Fibrils were formed by incubating the
monomeric α-synuclein in a nontreated polystyrene plate at quiescent
conditions. Samples were supplemented with 20 μM ThT and the
fluorescence intensity measured at different time points. The protein
concentration was 35 μM. (A) Raw data. Red: 10 mM MES/NaOH (pH
5.5), t1/2 = 13.4 h, two replicates. Blue:
in pure water, t1/2 = 38.0 h, four replicates.
The bold dots show the average of the replicates. Individual replicates
are shown with thinner dots. The t1/2 was
calculated by fitting a sigmoidal curve to the average data. (B) Normalized
data, same method and data as those in A. Cryo-TEM images of the α-synuclein
fibril samples collected after reaching the plateau in ThT fluorescence.
(C and D) α-Synuclein fibrils formed in water. (E and F) α-Synuclein
fibrils formed in 10 mM MES, pH 5.5.