[The cloning, expression, purification and identification of SARS virus S2 gene and study on its immunological characteristics].

Aim: To express S2 protein of SARS virus fused with Trx and then detect its reactivity to the sera from convalescent SARS patients.

Methods: The Trx-S2 fusion protein was expressed in E.coli. After purification, the Trx-S2 fusion protein was detected by Western blot with 6 serum samples of convalescent SARS patients and 6 serum samples of healthy donors.

Results: According to the SDS-PAGE analysis, the relative molecular mass (M(r)) of the Trx-S2 fusion protein is about 76 x 10(3). The fusion protein could react with all the sera from convalescent SARS patients but not with the sera from healthy donors.

Conclusion: The Trx-S2 fusion protein provides a basis for the research on its role in the course of SARS virus infection of host cells and preparation of recombinant vaccine against SARS virus.