Extended Data Fig. 7: Conformation of unmodified and monoglutamylated β tubulin tail peptides in solution.
From: Tubulin code eraser CCP5 binds branch glutamates by substrate deformation
a, b. HNHα J-couplings (JHNHα) (a) and sequential to intra HαHN NOE intensity ratios (b) for unmodified (blue) and monoglutamylated (red) βII(E440) tubulin tail peptides. Bars represent estimated errors. For J-couplings, the side chain cross peaks to the amide are all split by the same J-coupling. A subset of spectrally well-resolved residues were used to calculate for each residue the rms deviation of the J-coupling measured for the crosspeaks. The largest of these rms deviations, 0.4. Hz, was used as the estimated error for all the J-coupling values. A similar approach was used for the HαHN ratios by comparing the ratios using different multiplet components of the HαHN peaks for a subset of well-resolved residues, yielding an estimated error of 0.3. c, d. Alpha (c) and amide (d) regions of the NOESY spectrum of the unbound βII(E435) peptide. The two red-dashed ovals indicate where the contact signals would appear if the peptide were to adopt the conformation observed in the CCP5:Glu-P-peptide 1 structure. The off-diagonal NOE cross peaks in (d) were used for assignment of sequential residues, and their moderate intensity rules out beta-strand secondary structure. The splitting of the signals in the x-dimension corresponds to the HNHα J-coupling. e, f. HNHα J-couplings (JHNHα) (e) and sequential to intra HαHN NOE intensity ratios (f) for unmodified (blue) and monoglutamylated (red) βII(E435) tubulin tail peptides. Bars represent estimated errors determined as detailed in legend for panels (a) and (b). g, h. Alpha (g) and amide (h) regions of the NOESY spectrum of the unbound βI(E441) peptide. The two red-dashed ovals indicate where the contact signals would appear if the peptide were to adopt the conformation observed in the CCP5:Glu-P-peptide 1 structure. The off-diagonal NOE cross peaks in (b) were used for assignment of sequential residues, and their moderate intensity rules out beta-strand secondary structure. The splitting of the signals in the x-dimension corresponds to the HNHα J-coupling. i, j. HNHα J-couplings (JHNHα) (i) and sequential to intra HαHN NOE intensity ratios (j) for unmodified (blue) and monoglutamylated (red) βI(E441) tubulin tail peptides. Bars represent estimated errors determined as detailed in legend for panels (a) and (b).
