Evaluation of Immunogenicity, Protective Immunity on Aquaculture Pathogenic Vibrio and Fermentation of Vibrio alginolyticus Flagellin FlaC Protein

are the main pathogenic bacteria in aquaculture. The flagellin protein C (FlaC) of has good immunogenicity and the prospect of potential application in a vaccine. We aimed to evaluate the immunogenicity, protective immunity, and prokaryotic expression fermentation of FlaC protein for the vaccine in aquaculture. A molecular cloning method was used to construct the expression strain of FlaC protein, and the protein was purified with Ni-affinity chromatography. Polyclonal antiserum was prepared via mice immunized with the FlaC protein. The Western blot and enzyme-linked immunosorbent assay (ELISA) were used to check the specificity and titre of the antiserum. ELISA and pull-down assay detected the interaction between FlaC protein antiserum and . The immune protection function of FlaC protein was detected with mice actively immunized with FlaC protein and challenged by and . The optimal expression conditions for FlaC protein were detected using an L (3 ) orthogonal design model. The expression strain of FlaC protein was obtained successfully, and purified FlaC protein was prepared using a mice polyclonal antibody. The FlaC protein antiserum held a high specificity, and the titre was 13200. The antiserum directly interacted with and , and the FlaC protein demonstrated a significant immune protection function (50%) against infection and some immune protection function (41.66%) against . The optimal expression conditions for FlaC protein included a strain OD value of 0.8, final isopropyl-β-d-thiogalactoside (IPTG) concentration of 0.1 mmol/L, an inducing time of 8 hours, and an inducing temperature of 28°C. This study showed that the FlaC protein possesses a significant immunogenicity and immune protection effect and obtained the optimal fermentation conditions. It is expected to be a potential vaccine against and .