Synchrotron SAXS data from solutions of the N-terminal region of the Translocated Intimin Receptor (Tir76-180) in 100 mM Tris-HCl, 150 mM NaCl, 1 mM EDTA, pH 8 were collected on the B21 beam line at the Diamond Light Source (Didcot, UK) using a Pilatus 2M detector at a sample-detector distance of 3.69 m and at a wavelength of λ = 0.0954 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 50.00 μl sample at 12.6 mg/ml was injected at a 0.075 ml/min flow rate onto a Shodex KW403-4F column at 10°C. 520 successive 2 second frames were collected. The data were normalized to the intensity of the transmitted beam and radially averaged. The scattering intensities from SBB-tir elution peak region (21-frames) were buffer subtracted and averaged using the ScÅtter software (version 3Q) to produce the averaged SEC-SAXS profile. From this profile, the pair-wise distance distribution function, P(r), was obtained by indirect Fourier Transform with GNOM (version 5.0) using a momentum transfer range of 0.14 < s < 4.7 nm-1. The Rg values were estimated by applying the Guinier approximation in the range sRg < 1.3.
s, nm-1
