葡萄球菌肠毒素O表达及其生物学活性的初步分析

Translated title of the contribution: Expression and bioactivity of staphylococcal enterotoxin O

Ying Liu, Jin-Hai Huang*, Yue-Hui Sun, Li-Xia Zhang, Jian-Hua Wang, Shi-Wen Zhuang, Jing-Si Wang, Lin Li, Dan-Dan Xu

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Objective: To clone the mature peptide gene of seo, construct two kinds of prokaryotic fusion expression vector, obtain recombinant staphylococcal enterotoxin O(SEO) and evaluate its biological activity.

Methods: The seo gene was amplified from ZNZ2-3 strain of Staphylococcus xylosus by designed primers and it was cloned into fusion vector pGEX-6P-1 and pET28a. The soluble recombinant protein(GST-SEO) was expressed in E.coli BL21 host cells, the purified GST-SEO was obtained by a single step of affinity chromatography using Glutathinione Sepharose 4B colume. Another fusion protein(P28-SEO) with his-tag was expressed in E. coli BL21(DE3), the purified P28-SEO protein was harvested by nickel chelate affinity chromatography method. The antigenicity of recombinant SEO was tested by Western blot. The stimulating effects of recombinant SEO on mouse lymphocytes was tested by MTT. The activity of Caspase 3 and the apoptosis of DNA ladder were tested.

Results: The nucleotide sequence of the cloned seo gene was the same as that of reported in GenBank. The soluble recombinant protein GST-SEO was expressed at 25% expression level, and P28-SEO was 22%. The Western blot by GST-SEO-positive sera demonstrated that the recombinant SEO had good immunogenicity. The MTT assay of the enterotoxin activity showed that low dose of recombinant SEO stimulated the proliferation of mice spleen lymphocytes, higher doses will lead to apoptosis. 

Conclusion: Two of the recombinant SEO still have superantigen activity, and can lead to apoptosis of mice splenocytes.

Translated title of the contributionExpression and bioactivity of staphylococcal enterotoxin O
Original languageChinese (Simplified)
Pages (from-to)1094-1098
Number of pages5
JournalChinese Journal of Microbiology and Immunology
Volume29
Issue number12
DOIs
Publication statusPublished - 2009

Keywords

  • Bioactivity
  • Enterotoxin O
  • Staphylococcus

ASJC Scopus subject areas

  • Microbiology
  • Immunology
  • Virology

Cite this