Synchrotron SAXS data from solutions of cell division protein SepF (C-terminal domain) in 25 mM Tris, 100 mM NaCl, 10% glycerol, 1 mM EDTA, pH 8.5 were collected on the BM29 beam line at the ESRF (Grenoble, France) using a Pilatus3 2M detector at a sample-detector distance of 2.9 m and at a wavelength of λ = 0.1 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 1.00 mg/ml was measured at 20°C. 10 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.