SAXS Explorer: Protein Shape from Solution Scattering

Small-angle X-ray scattering (SAXS) is one of structural biology's key solution-phase methods — unlike X-ray crystallography or cryo-EM it needs no crystal and no freezing, just a dilute solution of the molecule tumbling freely in a beam. This simulator builds a coarse-grained bead model of a protein, computes its real orientation-averaged Debye scattering curve I(q) and Guinier plot in real time, and lets you watch both respond as you reshape the molecule between a compact globular fold, an elongated fold, and a fully denatured chain — the same diagnostic signatures (rising Rg, shrinking Guinier region, unchanged I(0)) a structural biologist reads off real synchrotron SAXS data to tell a folded protein from an unfolded one.