Fig. 3.

PIP2-dependent conformations of human ENTH hexamer. A: Mass spectra (acquired with 25 V in the trap cell of the Synapt) comprising the hexamer signals. Hatched-in areas represent the complex with PIP2 load as indicated and denote the m/z ranges used for ATD extraction as derived from the 75 V spectrum. To illustrate m/z range used the 20 + peak of the 75 V spectrum is depicted as inset with arrows denoting the ligand binding states as used for extraction of ATDs from the 25 V spectrum. B-D: ATDs representing the 22+, 21 + and 20 + charge states carrying 4–9 (see A for colors) PIP2 ligands. ATDs were normalized to total intensity, with those acquired with 75 V, offset by 2% along the y-axis. Vertical lines specify the drift times corresponding to the above-written CCS’s. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)