[Expression and identification of recombinant Staphylococcus aureus enterotoxin A].
OBJECTIVE
To clone the sequence of Staphylococcus aureus enterotoxin A (SEA) gene, construct its expression vector, and obtain high levels of recombinant Staphylococcus aureus enterotoxin A (rSEA) with high purity.


METHODS
The enterotoxin A gene was synthesized and inserted into the prokaryotic expressed vector pET28a possessing histiding-tag. The recombinant vector was transfected into E. Coli BL21 (DE3) after it had been verified by DNA sequencing. The strain can express the recombinant protein after the induction by the IPTG. The recombinant protein was purified by Ni-NTA His Bind affinity purification column.


RESULTS
The recombinant protein was obtained. SDS-PAGE showed that its molecular mass was about 30kD. The western bolt showed that it can specifically bind rabbit anti-SEA antibody. The BALB/c mouse was immunized by the recombinant protein followed by detection of anti-SEA antibody by ELISA. The results revealed that the protein has reactogenicity and immunogenicity, which provides the foundation for either the preparation of monoclonal antibodies or the further study of the immunological detection of SEA.


CONCLUSIONS
The rSEA expression vector was constructed successfully and highly expressed the rSEA protein.
Key Laboratory of Food Safety Risk Assessment, Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing 100021, China. wangjiahui@cfsa.net.cn
Jiahui
J
Wang
Key Laboratory of Food Safety Risk Assessment, Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing 100021, China.
Nan
N
Li
Key Laboratory of Food Safety Risk Assessment, Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing 100021, China.
Qing
Q
Shen
Key Laboratory of Food Safety Risk Assessment, Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing 100021, China.
Chunhui
C
Han
Key Laboratory of Food Safety Risk Assessment, Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing 100021, China.
Jing
J
Zhang
Key Laboratory of Food Safety Risk Assessment, Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing 100021, China.
Tao
T
Jiang
Key Laboratory of Food Safety Risk Assessment, Ministry of Health, China National Center for Food Safety Risk Assessment, Beijing 100021, China.
Fengqin
F
Li
D000818:Animals; D004768:Enterotoxins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005822:Genetic Vectors / Q000235:genetics*; D008807:Mice, Inbred BALB C; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D013211:Staphylococcus aureus
D004768:Enterotoxins; D011994:Recombinant Proteins; C026066:enterotoxin A, Staphylococcal