Figure 2. DDM-purified BmrC/BmrD is monodisperse.

(a) Size-exclusion chromatography of DDM-purified protein (∼0.3 mg) was performed as indicated in fig. 1d . Inset: Silver-stained SDS-PAGE of protein eluted at 10 ml. Black arrowhead, BmrD; grey arrowhead, BmrC. V_o: void volume. (b–d) Samples of nickel-affinity purified BmrC/BmrD (0.85 mg/ml) kept frozen at −80°C after flash freezing in liquid N₂, were thawed and analyzed by sedimentation velocity measurements at 20°C and 42000 revolutions per minutes. (b) Superposition of selected sedimentation profiles obtained at 278 nm and the corresponding fitted curves using continuous size distribution analysis. (c) Superposition of the residuals. (d) c(s) curves for the stock protein (continuous line) and the protein diluted 4 times in dialysis buffer (dashed line).