Extended Data Fig. 3. Resonance assignment and inter-residue correlations of membrane-bound BM2 at pH 7.5.

(a) 2D ¹³C-¹³C correlation spectrum with 55 ms CORD spin diffusion, measured at T_sample = 280 K. (b) Representative F2-F3 strips from the 3D CCC spectrum, showing various inter-residue correlations (assigned in red) that restrain the structure. The spectrum was measured using spin diffusion mixing times of 41 ms and 274 ms, at T_sample = 280 K. (c) 2D ¹³C-¹³C TOCSY spectrum with 7.7 ms mixing, collected at T_sample = 290 K. Residues 43–51 are dynamic and exhibit chemical shifts indicative of random coil conformation. (d) ¹³C CP spectrum preferentially detects immobilized residues while the ¹³C INEPT spectrum preferentially detects highly dynamic residues. These 1D spectra were measured at T_sample = 280 K.