Cloning and Expression of Bacillus anthracis Protective Antigen Domain a-1 in E. coli

Anthrax is a zoonotic disease in humans and animals. The disease is caused by Bacillus anthracis and the antibodies of domain a-1 protective antigen (PA) identify 62% of the antigens related to PA and most of their oligopeptides are observed in the AVP vaccines. In this experimental study, plasmid pXOI sequences with BamHI and XhoI enzymatic sites were amplified and cloned in the cloning vector and subcloned into the vector pET28a(+) and transformed into BL21(DE3) strain of E. coli after separation. The gene expression was performed by IPTG induction and after protein purification using affinity chromatography, the resulting antigen was injected into mice four times. Polyclonal antibody produced in the mouse serum was measured. Domain a-1 protective antigen cloned into the expression vector pET28a (+) was confirmed by PCR, enzyme analysis and sequencing. The produced recombinant protein was also confirmed by SDS-PAGE and western blot. Then, the produced antibodies were isolated from the mouse serum and confirmed by ELISA. The aim of this study was to generate antigen domain a-1 protective antigen of B. anthracis in E. coli. With regard to identification of antigen PA by the domain a-1 antibody and presence and stability of their oligopeptides for seven years or more in the AVP vaccines, it can be used in designing a vaccine for anthrax separately, in combination with the other domains (PA), or with adjuvants.