Region of
1H‐
13C‐HSQC spectra of
13C‐UbcH7 (blue),
13C‐UbcH7‐O‐Ub (black), and HHARI RING1‐bound
13C‐UbcH7‐O‐Ub (red) that includes the methyl (
13
CH
3) resonance of the surface‐exposed UbcH7 crossover helix residue, Ala110 (black arrow), is shown. The
13
CH
3 peak of Ala110 either broadens dramatically or shifts to an unknown position in the spectrum of
13C‐UbcH7‐O‐Ub (black) in the presence of HHARI RING1 it reappears at its position in
free UbcH7, consistent with disruption of closed UbcH7˜Ub conformations. Pairwise overlays and larger spectra are provided in
Appendix Fig S3.