Figure 6. NMR titration experiments of NBD1 by NBD2.

The HSQC spectra of NBD1 (220 μM) were titrated in the presence of 1 mM Mg-ATP by addition of 0:1 (black), 0.35:1 (blue), 1:1 (green) and 1.6:1 (red) molar equivalents of NBD2. The selected regions are centred on the backbone correlations of Gly⁷⁷⁰, Gly⁷⁷¹, Phe⁸⁶² and one Gly of His tag. On the top of each two-dimensional spectrum, the extracted ¹H spectrum at the ¹⁵N chemical shift of these residues is drawn, which has been normalized relative to the Gly His-tag signal.