Synchrotron SAXS data from solutions of the N-terminal RNA-binding domain of nucleocapsid protein complexed with the 5'-genomic RNA AU extension of SARS-CoV-2 in 25 mM HEPES, 75 mM KCl, 2.5 mM NaNO3, pH 7.2 were collected on the EMBL P12 beam line at PETRA III (DESY, Hamburg, Germany) using a Pilatus 6M detector at a sample-detector distance of 3 m and at a wavelength of λ = 0.124 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 90.00 μl sample at 4.5 mg/ml was injected at a 0.70 ml/min flow rate onto a GE Superdex 75 Increase 10/300 column at 25°C. 27 successive 1 second frames were collected through the elution peak of the sample. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted.
The quoted experimental molecular weight was determined using MALLS/RI measurements that suggest two NTD bind to one EXT-RNA. The SAXS indicates repulsive interparticle interference in the sample. Additional SEC-SAXS (unsubtracted frames) and MALLS/RI data are made available in the full entry zip archive.