Figure 4.

(A) Intensity ratio of NMR signals in the 3D hCANH spectra of back-exchanged deuterated Cp149 capsids vs. protonated Cp149 capsids. Unassigned and proline residues are shown as gray circles and residues with no signal in the deuterated sample are shown as red diamonds. The noise was adjusted to the same level for both spectra in CcpNmr before fitting the peak intensities and no normalization was applied. (B) Residues whose NH could not be back-exchanged in the deuterated capsids are shown in orange for chain C and in red for chain D on the X-ray structure 1QGT (Wynne et al., 1999).