[Prokaryotic expression and purification of recombination Salmonella invasion protein]

Abstract

Objective: To express recombinant Salmonella invasion protein A(InvA) in E. coli and purify it.

Methods: The invA gene of Salmonella was amplified by PCR from the Salmonella genome and cloned into expression vector pET-30c (+) to generate the pET-invA recombinants. They were comfirmed by restriction endonuclease digestion and sequence analysis. The verified recombinant was transformed into E. coli BL21 (DE3). After inducing with isopropyl-beta-D-thiogalactopyranoside (IPTG), the recombinant protein was purified via Ni-NTA affinity chromatography under denature conditions. The recombinant proteins were analyzed with SDS-PAGE and Western blot.

Results: The pET-invA recombinant for Salmonella was successfully constructed and the recombinant InvA protein was expressed in E. coli at a relatively high level. The SDS-PAGE results for the purified recombinant protein demonstrated that the purified protein had reached the electrophoresis purity.

Conclusion: The successful expression of the Salmonella InvA protein will be very helpful for the further study on its antigenicity, immunological activity, and the development of rapid detection methods for Salmonella strains.