Complete set of 15N-CEST and 15N-CPMG relaxation dispersion data together with Matlab fitting scripts for the paper entitled: "Unraveling structural transitions and kinetics along the fold switching Pathway of the RfaH C-terminal domain using exchange-based NMR"

The deposited files contain the complete set of 15N-CEST and 15N-CPMG data recorded for the isolated C-terminal domain of RfaH together with all relevant MatLab fitting scripts.
Abstract of paper: The bacterial transcriptional regulator RfaH comprises structurally and functionally distinct N- (NTD) and C- (CTD) terminal domains. The latter switches from a helical hairpin packed against the NTD to a 5-stranded b-roll upon displacement by RNA polymerase binding. Here we use 15N-CEST and 15N-CPMG relaxation dispersion NMR to probe fold switching intermediates sampled by the isolated CTD. In addition to the predominant (~76-77%), semi-stable b-roll conformation (state A), we identify 4 structurally and kinetically distinct states: A’, B, B’ and B”. State B is NMR observable with an occupancy of ~23%, exchanges slowly (tex ~ 300 ms) with the major A species, and comprises a largely unfolded ensemble with transient occupancy of helical (a5*) and b-hairpin (b1*/b2*) elements. Backbone chemical shift-based structure predictions using the program CS-ROSETTA suggest that the two transient structural elements within the B state may interact with one another to form a semi-compact structure. A’ (~0.35 %) is an off-pathway state that exchanges rapidly (tex ~ 1 ms) with state A and likely entails a minor localized conformational change in the b1/b2 loop. State B’ (~0.3 %) exchanges rapidly (tex ~ 1.2 ms) with state B and exhibits downfield 15N backbone shifts (relative to B) in the a5* region indicative of reduced helicity. Finally state B” (~0.05%) exchanges rapidly (tex ~ 0.8-1 ms) with either B’ (linear model) or B (branched model), displays significant differences in absolute 15N chemical shift from states B and B’, and likely represents a further intermediate with increased helicity along the fold-switching pathway.