Fig. 7.
19F CODEX data of membrane-bound TMD. (a) L493F-TMD in the POPC/cholesterol membrane. Representative S0 and S spectra are shown. (b) L493F-TMD in the POPE membrane. (c) L504F-TMD in the POPC/cholesterol membrane. (d) L500F-TMD in the POPC/cholesterol membrane. The data were acquired at 230 K under 8 kHz MAS. The percentages of α-helix and β-strand are taken from Table S1, and intermolecular 19F–19F distances in the β-sheet are fixed to 4.8 Å in the simulation. The CODEX intensities of L493F and L504F equilibrate to 0.33, indicating that the TMD is trimerized. The L500F CODEX decay is slower, indicating longer interhelical distances.