Recombinant Expression and Immunogenicity of the Outer Membrane Protein C of Escherichia coli O157:H7

Abstract:

Objective This study aims to investigate the immunogenicity of the outer membrane protein C (OmpC) of Escherichia coli (E. coli) O157:H7.Method The recombinant plasmids pET-28a-ompc and pET-22b-ompc-SUMO were constructed, and the recombinant protein OmpC was expressed and purified. Then, whether the target antigen of the 2G12 antibody prepared by E. coli O157: H7 cells was OmpC was determined.Result Two recombinant plasmids were successfully constructed and pET-28a-ompc was successfully expressed in E. coli BL21. The optimal induction conditions for expression of recombinant OmpC were 0.2 mmol/L IPTG, 37 ℃, and 12 h. The OmpC inclusion bodies containing His tags were obtained through elution with 800 mmol/L imidazole. The soluble OmpC was renatured by urea gradient dialysis and then eluted from the Ni-NTA column with 500 mmol/L imidazole.Conclusion OmpC in both the soluble form and the inclusion body form specifically react with the monoclonal antibody 2G12. The findings lay a foundation for the further preparation of high-affinity E. coli O157:H7 monoclonal antibodies with OmpC.