Extended Data Fig. 5. BM2 has similar conformations in POPE and POPC:POPG bilayers.

(a) 2D ¹³C-¹³C CORD spectra of BM2 in the two lipid membranes at low pH. (b) 2D ¹⁵N-¹³C correlation spectra of BM2 in the two lipid membranes at low pH. The POPE sample was measured at T_sample = 290 K for the 2D NC spectrum and 280 K for the 2D CC spectrum, while the POPC : POPG sample was measured at T_sample = 270 K to account for the lower phase transition temperature of this membrane. The lipid bilayers of both samples were in the gel phase, as assessed by ¹H spectra of the sample. Both spectra were measured under 14 kHz MAS on an 800 MHz spectrometer. (c) Chemical shift differences between the POPE and POPC:POPG samples at low pH. Residues in the α-helical TM domain and the β-strand do not show significant chemical shift differences.