Preparation and purification of recombinant protein fragment ompA240-356 from acinetobacter baumannii as a novel epitope for vaccination

Abstract

Acinetobacter baumannii has gained attention for years as a significant clinical problem due to the increase of antibiotic-resistant strain. Indeed, A. baumannii OmpA is one of the highly conserved membrane proteins among Gram-negative bacteria that has multiple roles in interacting with the host during infection, thereby representing an effective target for the development of novel an-tibacterial or vaccination therapies. Nowadays, finding suitable epitope-specific antigens inside the conserved proteins such as OmpA is a promising method for successful vaccination programs. Therefore, in the present study, the coding sequence of the 240 to 356 amino acid residues of A. baumannii OmpA (AbOmpA240-356) was cloned into the vector pET-28a and purified using nickel affinity chromatography. In addition, the anti-His tag antibody is used to validate its production. This system of protein expression and purification may be useful for further characterization of AbOmpA240-356 protein fraction. Therefore, this study can lead to the introduction of suitable candidates for the development of an effective vaccine based on OmpA against this bacterium for further analysis.