If multiple PDB files were uploaded by the user, in addition to profile calculation for each structure, the server will also run enumeration and fitting of multiple structures to the input profile. Here is an example:

• Input PDB files of DNA ligase III in several conformations (data from Cotner-Gohara et al. Biochemistry. 2010) input.zip
• Input profile file iq.dat
• FoXS output

In this example the crystal structure does not fit to the SAXS profile well (χ² = 230.2, green profile). Several conformations are needed in order to explain the data. In solution the protein exists as a population of closed and open states. The fit to data improves as more open states are added (bar plot and fit plot) and for 4 states the χ² value is 1.68. In the fit plot, the experimental data is shown as black dots, the best scoring single structure fit is green, the 2-state fit is red, the 3-state fit is blue, and the 4-state fit is cyan. Click on show/hide buttons to display/hide the corresponding profiles. The best scoring 2-, 3-, and 4-state models are shown below in the corresponding colors.