Fig. 4.

dUMP ligand state multiplets. Spectral overlays of apo, dUMP₁, and dUMP₂ allow visualization of chemical shift behaviors. WT apo and dUMP₂ peaks are shown in black and blue, respectively. The WT dUMP₁ peaks reconstructed from the mixed dimer chemical shifts are shown as red (bound subunit) and green (empty subunit) circles. These panels show the three classes of extreme chemical shift behaviors of the dUMP₁ state. A and B highlight supershifting of dUMP₁^bound, C highlights orthogonal shifting, D highlights reverse shifting of dUMP₁^bound, and E highlights supershifting (dUMP₁^empty) coupled with reverse shifting (dUMP₁^bound).