Prokaryotic expression and immunogenicity of IgG-binding protein of Streptococcus equi subspecies equi

Jungao Shao1 Huijiao Jiang1 Jianxin Chang1 Baojiang Zhang1 Shanchun Li1 Yan Su1

(1.College of Veterinary Medicine, Xinjiang Agricultural University, Urumqi, Xinjiang, China 830052)

【Abstract】To analyze the immunogenicity and protective ability of recombinant IgG-binding protein (EAG) of Streptococcus equi subspecies equi and to evaluate its value when used as equine vaccine antigen, EAG gene was amplified by PCR and inserted into pET-28a vector. The EAG recombinant proteins were expressed and purified to immune mice. The serum antibody and challenge protection were tested. The purified recombinant protein of EAG was 26 kDa, and the protein reacted specifically with positive serum of Streptococcus equi subspecies equi. The mice antibody level for EAG immunization group was 1:8 100. The immunological protection result showed that the protection rate of the EAG recombinant protein was 90%. The results suggested that the EAG protein has good immunogenicity and immunological protection, and it can effectively increase the humoral immune response and immunological protection of mice.

【Keywords】 Streptococcus equi subspecies equi; EAG protein; expression; immunogenicity analysis;


【Funds】 National Science and Technology Support Program (No. 2012BAD46B01) National Science and Technology Support Program(No.2012BAD46B01)

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(Translated by HE Wei)


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This Article


CN: 11-1998/Q

Vol 32, No. 05, Pages 577-583

May 2016


Article Outline



  • 1 Materials and methods
  • 2. Results and Analyses
  • 3 Discussion
  • References