Synchrotron SAXS data from solutions of saposin-A plus MNA C12 in 25 mM Tris-HCl, 150 mM NaCl, pH 7.5 were collected on the 12ID-B SAXS/WAXS beam line at the Advanced Photon Source (APS), Argonne National Laboratory (Lemont, IL, USA) using a Pilatus 2M detector at a wavelength of λ = 0.0932 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). In-line size-exclusion chromatography (SEC) SAS was employed. The SEC parameters were as follows: A 100.00 μl sample at 7 mg/ml was injected at a 0.20 ml/min flow rate onto a GE Superdex 75 Increase 5/150 column at 25°C. 624 successive 1 second frames were collected. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted.