Figure 5

Membrane extraction profile of small VSA proteins. Trophozoite infected erythrocytes of the 3D7 strain were lysed by hypotonic lysis (HL) and the pellet fraction was separated by centrifugation. The membrane pellet fraction was extracted with salt (Salt), carbonate (Carb), Triton X-100 (TX), SDS (SDS) or urea (Urea) containing buffers, respectively, and separated into a soluble (SN) and an insoluble (P) fraction by centrifugation. Equivalents of 1 × 10⁷ cells were loaded in each lane. a Proteins were visualized by western blot analysis with the antibodies α-RIF40.2, α-RIF44, α-RIF50, a mixture of all α-STEVOR sera and α-PfMC-2TM-SC. b To control extraction performances, blots were probed with the antibodies α-CIDR, α-ATS, α-SBP1, α-Exp1, α-Spectrin and α-Glycophorin A/B directed against proteins with known solubilities.