Structural parameters derived from SAXS data.

Rg, Dmax and MMexp are the radius of gyration, maximum size and molecular mass respectively calculated from SAXS data. MMseq is the molecular mass of Gth calculated from the primary structure of the protein with two associated sugar chains.χ pre-, χ post-, χ pre/post, χ pathway A, χ pathway B and χ pathways A & B denote the discrepancy between experimental data and scattering curves calculated from Gth pre- and post-fusion protomers, combination of both, and combinations using model conformations from trajectory A, trajectory B and a combination using all the conformations from pathways A and B. ND: not determined.