Recombinant CS/D constructs.

A, Cartoon representation of the native P. falciparum CSP consisting of a signal sequence and GPI anchor sequence (red), N-terminal region (green), NVDP and NANP repeats (blue) and a cysteine rich C-terminal region (purple). The expressed constructs (CS/A, CS/C, CS/D and CS/E), their PfCSP-specific start and end residues, and the relative positions of the five cysteine residues (“C”) are shown. B, SDS-PAGE shows relative expression levels (arrows) in un-induced (Un) and induced (In) E. coli cells producing CS/C, CS/D and CS/E.