[Expression and stability of fragment of Plasmodium merozoite major surface protein 1 in recombinant attenuated Salmonella typhimurium].
OBJECTIVE
To determine the invasive ability of recombinant attenuated Salmonella typhimurium X4064 (pQEM1) strain containing gene fragment of Plasmodium falciparium merozoite surface protein 1 (MSP1), the stability of its plasmid, and its re-expression.


METHODS
BALB/c mice were fed with recombinant attenuated S. typhimurium containing No. 1 gene fragment of P. falciparium MSP1 by gastric tube. Plate incubation, plasmid endonuclease analysis and Western blot were used to identify the recombinant attenuated S. typhimurium strains isolated from mice and the ability of re-expression, and its growth were determined in vitro.


RESULTS
The attenuated strain X4064 of S. typhimurium isolated from mice contained recombinant plasmid pQEM1, no. 1 MSP1 fragment of P. falciparium was expressed in vitro in S. typhimurium X4064 (pQEM1) strain, and its growth curve of X4064 (pQEM1) strain in mice was basically similar to that of X4064.


CONCLUSIONS
The recombinant plasmid pQEM1 could steadily exist in the X4064 strain of S. typhimurium, without influence on its invasion into host cells. X4060 (pQEM1) strain isolated from infected mice still had the ability to re-express M1 protein.
Qian
F
F
Department of Parasitology, The Second Military Medical University, Shanghai 200433.
Guan
W
W
Fang
J
J
Jiang
C
C
D000818:Animals; D020066:Merozoite Surface Protein 1 / Q000096:biosynthesis*; D051379:Mice; D008807:Mice, Inbred BALB C; D010446:Peptide Fragments / Q000096:biosynthesis*; D010957:Plasmids; D011994:Recombinant Proteins / Q000096:biosynthesis*; D012486:Salmonella typhimurium / Q000235:genetics* / Q000254:growth & development
D020066:Merozoite Surface Protein 1; D010446:Peptide Fragments; D011994:Recombinant Proteins