Synchrotron SAXS data from solutions of SARS-CoV-2 non-structural protein 7-8 (nsp7-8) polyprotein dimer in 50 mM Tris, 500 mM NaCl, 5% glycerol, and 1 mM TCEP, pH 8 were collected on the BioCAT 18ID beam line at the Advanced Photon Source (APS), Argonne National Laboratory (Lemont, IL, USA) using a Pilatus3 X 1M detector at a sample-detector distance of 3.6 m and at a wavelength of λ = 0.1033 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). In-line co-flow (sheath cell) size-exclusion chromatography (SEC) SAS was employed. The SEC parameters were as follows: A sample at 8 mg/ml was injected onto a GE Superdex 200 Increase 10/300 column at 22°C. 1300 successive 0.500 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.
SEC-MALS-SAXS. Size separation used a 1260 Infinity II HPLC (Agilent Technologies). UV data was measured in the Agilent, and MALS-DLS-RI data by DAWN HELEOS-II (17 MALS + 1 DLS channels) and Optilab T-rEX (RI) instruments (Wyatt Technology).
s, nm-1
