In Vitro Expression of Viral Coat Protein in Prokaryotic System and Its Purification

Abstract

Generally, the quality of polyclonal antibodies (PAbs) depends on the purity of the virus preparation used for immunization. But in most cases, PAbs raised against the purified virus cross reacts with host proteins which limit their use in serological assays. To overcome these limitations, in vitro expression of viral coat protein in a bacterial system is a good alternative to produce large quantity of the quality coat protein. The purified in vitro expressed protein has been used for the production of polyclonal antiserum for large number of viruses. Bacterial expression of viral proteins is simple, fast and economical for generating high amount of purified proteins with minimal post-translational modifications. The method involves amplification, cloning and expression of the coat protein of the virus in a prokaryotic system followed by purification of expressed coat protein that are then used as antigen for antiserum production for immunodiagnosis of plant viruses.