Figure 7.

Disorder-order transitions in PDK1 αB and αC helices function as conformational switches for kinase activation. Stacked mass spectral envelope plots for two overlapping peptides, 115–130 and 122–134, spanning αB and αC helices in different states at deuterium exchange time t = 0.5 min. Shift in centroids are relative to the undeuterated (aqueous) peptide. Bimodal isotopic distributions can be resolved into low-exchanging (blue) and high-exchanging states (orange). See also Figs. S4 and S5. To see this figure in color, go online.