Fig 1.

Expression and purification of rPfMSP8 and rPfMSP8(ΔAsn/Asp). (A) Schematic depiction of the amino acid sequences of rPfMSP8 (567 residues) and rPfMSP8(ΔAsn/Asp) (373 residues) in relation to the native sequence of P. falciparum (FVO) MSP8. Positions of the conserved cysteine residues are indicated by the red lines. (B) Coomassie blue-stained 10% SDS-polyacrylamide gel containing lysates of E. coli (reduced) expressing the rPfMSP8 and rPfMSP8(ΔAsn/Asp) at the time of induction (T0) or 3 h postinduction (T3) and nickel-chelate affinity-purified proteins (3 μg per lane) under reducing (R) and nonreducing (NR) conditions. (C) Immunoblot analysis of the purified proteins (0.1 μg per lane) under reducing (R) and nonreducing (NR) conditions probed with anti-His tag monoclonal antibody. Normal mouse serum (NMS) served as a negative control. Molecular weight markers in kilodaltons (kDa) are indicated.