[Expression of predicted B cell epitope peptide in S2 subunit of SARS coronavirus spike protein in E.coli and identification of its mimic antigenicity].

Feng, Yu; Wan, Min; Wang, Xuan-jun; Zhang, Pei-yin; Yu, Yong-li; Wang, Li-ying

AIM To study the expression of predicted B cell epitope peptide in S2 subunit of SARS coronavirus spike protein in E.coli and its mimic antigenicity to S2 protein. METHODS B cell epitopes in S2 subunit of SARS coronavirus spike protein was predicted using DNAStar software. The cDNA sequence encoding the B cell epitope peptide was constructed artificially by PCR and then cloned into the downstream of chaperone 10 gene in vector pET28a(+) to construct pET28-chap10-S2epi plasmid. The fusion protein, chap10-S2epi, was expressed in E.coli BL21(DE3) and identified by SDS-PAGE and Western blot. The rabbit was immunized by purified Chap10-S2epi for the preparation of antiserum, which was used to identify the mimic antigenicity of Chap10-S2epi to S2 protein by ELISA. RESULTS Chap10-S2epi fusion protein was successfully constructed and expressed in E.coli. The antiserum from the animal immunized by Chap10-S2epi recognized full length of SARS coronavirus S2 spike protein. CONCLUSION The predicted B cell epitope peptide of SARS coronavirus S2 spike protein can induce the antigenicity of S2 protein, which provides some fundamental data for developing engineering vaccine against SARS coronavirus infection.