Cloning and expression of the Vibrio cholera recombinant FlaA Flagellin protein and evaluation of its antigenicity characteristics

Background: Vibrio cholera is an important agent causing cholera in human. The expression of Flagellum and the movement of the bacterium are critical in the colonization and virulence of Vibrio cholera. FlaA gene is one the five genes encoding Flagellin which plays an important role in the activity and movement of the bacterium and its colonization which has a significant role in its immunogenicity. The aim of this study was to express and produce the recombinant FlaA protein in E.coli using Western blot method. Materials and Methods: In this experimental study, FlaA gene was proliferated by PCR method using the specific primers and cloned with BamHI and Xhol in pTz57R/T. Then it was proliferated and sequenced in DH5a vector of E.coli. The cloned FlaA gene was inserted into pGEX4T-1 vector. The cloned vector was transformed to BL21-DE3 of E. coli and successfully expressed by induction of IPTG. The expressed protein was purified by GST affinity resin. For preparation of the primary antibody, the purified recombinant protein was injected to rats. Western blot assay method was used for determining the antigenicity of the recombinant FlaA. Results: Determination of gene sequencing showed that this gene has been proliferated properly and the antibody used in Western blot verified the production of the recombinant protein. Conclusion: The results of this study demonstrate that FlaA protein is immunogenic and can be evaluated in vaccine designing and as a diagnostic tool for detection of cholera infection.