Figure 1.
SEC–MALS analysis of Vps75 suggests it forms a stable tetramer under physiological conditions. (A) SEC–MALS elution profiles of full-length Vps75 in 150 mM (blue) and 500 mM (red) sodium chloride. The molar mass over elution peaks is shown in corresponding colours. (B) As in (A) except Vps75 lacking the unstructured C-terminal domain was analysed (residues 1–223). The association of soluble Vps75 with Vps75 dimers immobilized to a probe via a biotin linkage was measured using bio-layer interferometry. Changes in the response units were measured in the presence of increasing concentrations of soluble Vps75 dimers (C). A fit to the binding response data was then used to calculate the dissociation constant, Kd (D).