CRYSOL
is a program for evaluating the solution scattering from macromolecules with known atomic structure and fitting it to experimental scattering curves from Small-Angle X-ray Scattering (SAXS). As an input one can use a PDB file with an X-ray or NMR structure of a protein or a protein-DNA(RNA) complex.
The program uses multipole expansion of the scattering amplitudes to calculate the spherically averaged scattering pattern and takes into account the hydration shell. Given SAXS experimental data, CRYSOL can fit the theoretical scattering curve by minimizing the discrepancy (chi-square value).
Fitting is done by varying three parameters: (i) average displaced solvent volume per atomic group (ii) contrast of the hydration shell (iii) relative background
crysol [PDBFILE] [EXPDATA] [OPTIONS]