Figure 2.
hUbc13 backbone amide chemical shift changes during titration with TRAF6-RD. (A) Superposition of hUbc13 1HN–15N HSQC NMR spectra collected for [TRAF6]/[hUbc13] ratios: (red) 0:1, (blue) 7.2:1. Various cross-peaks affected by complex formation are labeled according to residue number. (B) Per-residue plot of chemical shift perturbations for 7.2:1 [TRAF6]/[hUbc13]. The mean (0.07) and cutoff for one standard deviation from the mean (0.17) are included. (C) Cartoon (top) and surface (bottom) representations of hUbc13. For the cartoon representation, residues that experience chemical shift perturbation greater than one standard deviation from the mean upon titration of TRAF6 are red. The surface representation is colored with negatively charged atoms from Glu and Asp in red; positively charged atoms from Lys, His, and Arg in blue; and side-chain atoms from hydrophobic residues (Ala, Val, Leu, Ile, Phe, Tyr, Met, and Pro) in yellow. Atoms from remaining residues and those from the main chain are white.