Expression and purification of Plasmodium falciparum MSP-1(42): A malaria vaccine candidate.
The C-terminal 42.10(3) Da portion of the merozoite surface protein (MSP-1) of the human malaria parasite Plasmodium falciparum is of interest, not only because it may constitute an essential part of a future anti-malaria vaccine, but also due to its role during the infection of erythrocytes by the parasite. We have cloned and expressed two synthetic DNA sequences encoding the two prototypic MSP-1(42) variants in E. coli. When over-produced, both proteins form insoluble aggregates which were isolated in high purity and yield. After solubilisation and refolding in vitro, both proteins were purified to homogeneity by a three-step procedure applying Ni-chelate, size exclusion and immuno-affinity chromatography. After purification, both proteins meet key criteria of preparations for clinical use. First, conformational studies suggest proper folding of the proteins, particularly in the region containing two EGF-like domains. Polyclonal serum raised against E. coli produced MSP-1(42) recognizes native MSP-1 in Plasmodium infected erythrocytes as shown by immunofluorescence.
Epp
Christian
C
Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), Im Neuenheimer Feld 282, D-69120, Heidelberg, Germany.
Kauth
Christian W
CW
Bujard
Hermann
H
Lutz
Rolf
R
D000595:Amino Acid Sequence; D000818:Animals; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D017780:Malaria Vaccines / Q000235:genetics* / Q000302:isolation & purification*; D020066:Merozoite Surface Protein 1 / Q000737:chemistry*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D010963:Plasmodium falciparum / Q000276:immunology*; D017386:Sequence Homology, Amino Acid
D017780:Malaria Vaccines; D020066:Merozoite Surface Protein 1; D010446:Peptide Fragments