Fig. 6: HDX-MS reveals different conformations in A53E compared to WT and A53T aSyn.

Bars represent differences in deuterium uptake of peptides along the sequence of differently compared aSyn mutants with the N-terminus region in blue, the NAC region in yellow, and the C-terminus in red. Negative values represent increased deuterium uptake in the mutant (a–c) or in the calcium bound state (d–f), correlating to more solvent exposure, and less hydrogen bonding. The start and end of each peptide is marked on the x-axis (from aSyn peptide map see Supplementary Fig. 11). Peptides containing the mutation were not comparable to WT aSyn and were removed from the data set, indicated by blank regions. Difference in deuterium uptake (Da) between a WT and A53T aSyn, b WT and A53E aSyn and c A53T and A53E aSyn showed no significant differences throughout the sequence. In the presence of calcium, as previously shown in Fig. 2c, d WT aSyn becomes significantly deprotected at the N-terminus and the NAC region, and more solvent protected at the C-terminus. e Similarly, A53T aSyn is significantly deprotected at the N-terminus and the NAC region upon calcium addition, and at the same time becomes solvent protected at the C-terminus. f A53E aSyn also becomes solvent protected at the C-terminus upon calcium addition but no significant changes are observed at the NAC region and most of the N-terminus. The grey trace signifies the error (1 s.d.) of six replicates collected per condition. Data acquired at each peptide were subjected to an unpaired Student’s t-test with alpha set to 1%. Each row was analysed individually, without assuming a consistent SD, individual two-tailed p values are presented in Supplementary Tables 1–5 and significant differences where p-values are ≤0.01 are presented by a *. Individual replicate values for deuterium uptake are presented in Supplementary Figs. 25–27.