FIGURE 4.
PRE experiments confirm the orientation of the Pex5-(57–71) peptide bound to Pex14-NTD observed in the NMR structure. Comparison of experimental (blue squares) and back-calculated PRE data (black circles, error bars indicate variations across the NMR ensemble) obtained for Pex14-NTD in complex with C-terminally (left panel) and N-terminally (right panel) spin-labeled Pex5 peptides. In both cases, there is excellent agreement between experimental and back-calculated values, as judged from the low value of the quality factor QPRE. The paramagnetic spin label was attached to a terminal cysteine residue added to the Pex5 peptide (shown in red).