Fig. 2.
Salt dependence of the α-syn aggregation kinetics. Aggregation kinetics monitored using thioflavin-T (ThT) fluorescence starting from 5 μM α-syn monomer in the presence of two different seed concentrations, (a) 0.005 and (b) 0.05 μM, were monitored at salt concentrations ranging from 0 to 1,200 mM NaCl in 10 mM MES buffer pH 5.5 at 37°C and under quiescent conditions with color codes shown in panel (a). The figures show the median traces of at least three experimental repeats. (c) t 1/2, the time at which the ThT fluorescence has reached 50% of the total fluorescence amplitude, as a function of salt concentration for both seed concentrations. Normalized aggregation kinetic traces for 5 μM α-syn monomer in the presence of (d) 0.005 μM and (e) 0.05 μM seed at salt concentrations ranging from 0 to 120 mM NaCl. The figures show the experimental repeats dotted with the fits as solid lines. (f) Fitted values of the rate constant product k2k+ as a function of salt concentration.