Fig. 4: Agreement between simulations and SAXS or PRE data for IDPs.

Mean radii of gyration (R_g) calculated from simulations plotted against R_g determined from Guinier fits to SAXS data for (a) simulations with unmodified Martini 3, (b) simulations with protein-water interactions in Martini 3 rescaled by λ_PW = 1.10, and (c) simulations with protein-protein interactions in Martini 3 rescaled by λ_PP = 0.88. Error bars on the experimental R_g-values were determined using Atsas AUTORG and represent a fitting error from the Guinier fit plus a standard deviation over possible selections of the Guinier region. The diagonal is shown as a dashed line and a linear fit with intercept 0 weighted by experimental errors is shown as a solid line. Pearson correlation coefficients (r_P) with standard error of the mean from bootstrapping with 9999 resamples are shown on the plots. d Reduced χ² to experimental SAXS intensities given by SAXS intensities calculated from unmodified Martini 3 simulations (blue) and Martini 3 simulations with protein-water interactions rescaled by λ_PW = 1.10 (orange) or protein-protein interactions rescaled by λ_PP = 0.88 (green). Mean and standard error of the mean over all 12 proteins are shown on the plot. Note the logarithmic scale for \({\chi }_{r}^{2}\). e Reduced χ² to experimental PRE NMR data given by unmodified Martini 3 simulations (blue) and Martini 3 simulations with protein-water interactions rescaled by λ_PW = 1.10 (orange) or protein-protein interactions rescaled by λ_PP = 0.88 (green). Note the logarithmic scale for \({\chi }_{r}^{2}\). f Representative conformation of Tau_K25 with an R_g corresponding to the average R_g in (blue) simulations with unmodified Martini 3, (orange) simulations with protein-water interactions in Martini 3 rescaled by λ_PW = 1.10, and (green) simulations with protein-protein interactions in Martini 3 rescaled by λ_PP = 0.88. All simulations with λ_PW=1.10 were taken from Thomasen et al.⁷. Source data are provided as a Source Data file.