Figure 2
NMR data for the titration of [ U -15N]-labeled HscB with apo-IscU. Combined chemical shift changes (ΔδHNIscU) of selected residues are plotted as a function of IscU/HscB molar ratio for wild-type HscB (black diamonds), HscB(D103A) (yellow circles), HscB(E100A) (green triangles), and HscB(L96A) (red squares). ΔδHNIscU values are reported as the combination of changes in the proton (HIscU) and nitrogen (ΔδNIscU) dimensions according to ΔδHNIscU = [(ΔδHIscU)2 + ΔδNIscU/6)2]1/2 [29]. ΔδHIscU and ΔδNIscU are calculated relative to the free form of each protein.