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 antibacterial 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.