Synchrotron SAXS data from solutions of polΔcat-primΔ2C in the absence of substrate in 20 mM HEPES, 150 mM NaCl, 5 mM MgCl2, 1 mM TCEP, pH 7.5 were collected on the 12.3.1 (SIBYLS) beam line at the Advanced Light Source (ALS; Berkeley, CA, USA) using a Pilatus3 X 2M detector at a sample-detector distance of 1.5 m and at a wavelength of λ = 0.103 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 60.00 μl sample at 5 mg/ml was injected at a 0.65 ml/min flow rate onto a Shodex LW-803 column at 23°C. 500 successive 3 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.
s, nm-1
