[Inducible expression of MSP1 gene of Plasmodium falciparum by a tetracycline controlled promoter in Salmonella typhi CVD908 strain].
OBJECTIVE
To investigate the inducible expression of MSP1 gene of Plasmodium falciparum in Salmonella typhi CVD908 vaccine strain using a tetracycline-controlled PLtetO promoter.


METHODS
The recombinant plasmid pZE11/MSP1-42 was transferred into the CVD908/tetR strain by electroporation. Detections of the expression of MSP1-42 both in vitro and in vivo were carried out using SDS-PAGE, Western blot and immunofluorescence assay.


RESULTS
The CVD908/tetR/MSP1-42 strain was constructed and the expression of MSP1-42 was dependent on the presence of tetracycline in vitro. The yield of the inducible expression was higher than that of constitutive system. Moreover, the MSP1-42 was expressed in the liver and spleen of mice inoculated with the CVD908/tetR/MSP1-42 strain in the presence of tetracycline, whereas no expression was detected in the absence of the inducer.


CONCLUSIONS
The recombinant Salmonella typhi strain which expresses the MSP1-42 fragment of Plasmodium falciparum induced by tetracycline has been established successfully.
Qian
F
F
Department of Etiological Biology, Second Military Medical University, Shanghai 200433, China.
Pan
W
W
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003001:Cloning, Molecular; D015870:Gene Expression; D020066:Merozoite Surface Protein 1 / Q000096:biosynthesis / Q000235:genetics*; D051379:Mice; D010957:Plasmids / Q000235:genetics*; D011401:Promoter Regions, Genetic; D012485:Salmonella typhi / Q000235:genetics*; D013752:Tetracycline / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D020066:Merozoite Surface Protein 1; D013752:Tetracycline