NMR Analysis of αTS Dynamics

The NMR experiments were conducted and analyzed as previously described (Axe and Boehr, 2013 (link); O’Rourke et al., 2018 (link)). Protein samples were exchanged into NMR buffer (50 mM potassium phosphate, pH 7.8, 2 mM DTT, 0.2 mM EDTA, and 10% ²H₂O) and contained 1.0 mM ²H, ¹⁵N-labeled αTS, 10 mM indole (Thermo Fisher) and/or 20 mM G3P (Sigma Aldrich) where appropriate. ¹⁵N R₂ relaxation dispersion experiments were collected and analyzed according to previously established procedures (Loria et al., 2008 (link); O’Rourke et al., 2018 (link)). Briefly, data was collected at 283 K on 600 and 850 MHz Bruker Avance III spectrometers using previously described pulse sequences (Loria et al., 1999 (link)) and data analyzed using the computer program GLOVE (Sugase et al., 2013 (link)).