Expression and cloning of recombinant VP2 protein of canine parvovirus in bacterial and cell-free prokaryotic systems

Background: The importance of VP2 protein of canine parvovirus to bind to human cancer cells and to detect the virus in veterinary detection kits has motivated a lot of research on the production of this protein. In this project, a surface gene of canine parvovirus (VP2) was cloned and expressed in a prokaryotic vector system and its expression was optimized in a specific cell-free prokaryotic expression system. Materials and Methods: In this experimental study, plasmid pET-21aVP2 was constructed by cloning the PCR product of VP2 gene of canine parvovirus into the plasmid expression pET-21a vector. The best sequence was analyzed through PCR and it was followed by confirmation with sequencing and restriction digestion. To produce VP2 protein, plasmid pET-21aVP2 was transferred into Escherichia coli, Rosetta (DE3) strain, and the expression of this protein was induced by IPTG. The production of VP2 protein in both systems was evaluated using SDS PAGE technique. The expressed protein was checked with monoclonal antibody against VP2 protein by Western blotting technique. Results: Successful cloning of VP2 protein was confirmed by enzymatic digestion and sequencing. The expression of VP2 protein in bacterial and cell-free prokaryotic systems was verified by SDS PAGE and the specific band in Western blotting also confirmed the VP2 protein. Conclusion: The results of this study showed that VP2 gene was amplified in the cloning phases and it was successfully cloned in the expression vector. Protein expression was confirmed in both bacterial and cell-free prokaryotic systems.