Figure 1.

Projection of chemical shifts onto a DQSQ spectrum using the chemical shift statistics from the BMRB database³⁷ and Platzer et al.³⁶. Errors reflect the standard deviation from the chemical shift assignments of these residues. Chemical shifts of aspartate and glutamate side chains were taken from Platzer et al.³⁶ because both protonated and deprotonated chemical shifts were reported. The structures of the side chains of aspartate, asparagine, glutamate, and glutamine are color coded with the DQSQ plot.