Fig. 4.
Examples of SDS-PAGE analyses of purification procedures as detailed in Materials and Methods. (A) Isolation of Vpu2–81 inclusion bodies. Lane 1, the total cell protein 4 h after induction for expression; lanes 2 and 3, discarded soluble fractions; lane 4, inclusion bodies fraction. (B) Purified Vpu2–81. (C) Purification of Vpu28–81. Lane 1, mixtures after CNBr cleavage reaction; lanes 2 and 3, the separation of trpΔLE from fusion and Vpu28–81; lanes 4 and 5, the separation of Vpu28–81 from the fusion protein by size-exclusion chromatography.