Fig. 2
Analysis of the solution conformation of Synechocystis apo-CTD dimers using SAXS. a Kratky plot showing that apo-CTD is represented by particles with a globular core and flexible termini/loops. b Ab initio shape reconstruction using DAMMIF. Three best-fitting DAMMIF models are shown superimposed to reveal the common core (DAMFILT core, cyan spheres). c CORAL-derived structural model of the A-type apo-CTD dimer obtained upon modeling of the flexible N- (23 residues) and C-terminal (12 residues) tails in order to minimize the discrepancy between the experimental and theoretical SAXS curves calculated from the model. The CORAL model overlaid with the DAMFILT core (cyan spheres) from b is shown by ribbons colored by gradient from blue (N-terminus) to red (C-terminus), with the flexible termini represented by Cα atoms (gray spheres). d Fitting of the experimental SAXS profile for apo-CTD by the best-fitting CORAL-derived models corresponding to either A-type (dark blue; χ2 = 1.14, CorMap = 0.16) or F-type (light blue; χ2 = 2.51, CorMap = 0.00) dimers
