SDS-PAGE and Western Blotting of Plasmodium falciparum Proteins

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting are complementary methods for separating and detecting the presence of a specific protein from a complex mixture. Proteins, from a cell extract, for example, are separated electrophoretically through a polyacrylamide gel. Next, these are transferred onto a nitrocellulose membrane by electrical current, preserving the original banding pattern from the gel. The membrane is probed with an antibody specific for the protein of interest, forming an antibody-antigen complex that can be visualized by a variety of techniques. This chapter outlines a procedure for the analysis of a specific protein(s) from cultured, asexual stage Plasmodium falciparum by SDS-PAGE and Western blotting, using a minigel system. The entire procedure can be completed in one day. Most of the methods outlined below are applicable to proteins from a wide variety of sources.