Figure 7
σSSTM-induced perturbations in NMR spectra of CrlSTM.
(a) Selected region of the 1H-15N TROSY spectrum of 15N2H-labeled CrlSTM in the absence (black) and presence of 0.25 equivalents of unlabelled σSSTM (green) showing the intensity decrease of amide signals for some residues like N43. (b) Plot of intensity ratios as a function of residue number. Background colours indicate the boundaries of CrlSTM secondary structures (red for α-helices, blue for β-strands). The mean value and mean minus one standard deviation (SD) are shown in continuous and dashed lines. (b) The nitrogen atoms of residues with the lowest intensity ratios (I/I0 < mean—SD) in the presence of σS are shown in green spheres on the NMR structure of CrlSTM, represented by three conformers to illustrate the structural variability in loop regions (in red). Two critical residues for σSSTM binding, D36 and R51, are represented in blue sticks.
