Extended Data Fig. 1: SSNMR analysis of structural and dynamic rearrangements in the cyt c peroxidase complex with MLCL.
From: Anomalous peroxidase activity of cytochrome c is the primary pathogenic target in Barth syndrome
a, Region from the 2D CP-DARR spectrum of 15N,13C-labeled cyt c bound to DOPC:MLCL(L)3 (1:1; blue). Overlaid red contours show simulated peak patterns constructed from the solution NMR shifts of the N- and C-terminal α-helices (BMRB ID 25908). b, 2D 15N-13C NCA ssNMR spectrum of the same sample, along with a corresponding simulated spectrum for the N- and C-terminal α-helices. The simulated peaks from the blue foldon coincide with strong peaks in the experimental ssNMR spectra. c, 2D (CP-based) 15N-13C NCA ssNMR spectrum of membrane-bound cyt c, alongside the analogous simulated spectrum (d) for cyt c in solution (BMRB ID 25908). Key resonances missing in the experimental spectrum (c) are indicated with green circles; these mostly belong to the Ω-loop D (for example Met80 and Ile81). These 2D NCA ssNMR spectra were acquired at 253 K and 10 kHz MAS. e, 1D 13C INEPT, CP, and direct excitation spectra of 15N,13C-labeled cyt c bound to DOPC:MLCL(L)3 (1:1), measured at 278K. These ssNMR spectra detect flexible (INEPT), rigid (CP), or both (direct excitation) sample components. The liquid crystalline lipids contribute many peaks to the INEPT spectrum (marked with blue arrows), while the labeled protein dominates the other two spectra. f, Overlay of 2D INEPT-TOBSY spectra for 15N,13C-labeled cyt c bound to MLCL/DOPC (blue) and CL/DOPC (red) vesicles. Cross-peaks stem from the labeled protein and must reflect flexible residues. Many more (and stronger) peaks are seen for MLCL-bound cyt c.
