Figure 2.

Two-dimensional solid-state NMR ¹H–¹⁵N dipolar coupling/¹⁵N chemical shift correlation PISEMA planes from uniformly ¹⁵N-labeled full-length Vpu in oriented lipid bilayers. (A) Plane extracted from a three-dimensional ¹H chemical shift/¹⁵N dipolar coupling/¹⁵N chemical shift spectrum at the ¹H chemical shift frequency of 15.9 ppm. (B) Two-dimensional PISEMA spectrum. (C–G) Two-dimensional PISEMA spectra calculated for a 17-residue α-helix, with uniform dihedral angles (φ = −57°; ψ = −47°) for the transmembrane orientations 0° (C), 10° (D), 15° (E), 20° (F), and 30° (G) between the long axis of the transmembrane helix and the normal to the membrane plane. The blue box highlights the spectral region occupied by resonances in the two-dimensional PISEMA spectrum from residues in the single transmembrane helix of Vpu.