EXPRESSION, PURIFICATION, AND CHARACTERIZATION OF RECOMBINANT V, THE NEWCASTLE DISEASE VIRUS NON-STRUCTURAL PROTEIN

Abstract

Poultry industry facing problems in vaccination of chicken against Newcastle disease virus (NDV) due to the difficulty of differentiating the vaccinated and naturally infected birds. If we could find a key marker that could differentiate, we would bring a great achievement to the industry. NDV genome contains genes for six major structural proteins and two non-structural proteins. The non-structural protein V could be a useful antigen for differentiating chickens infected with NDV from those vaccinated with inactivated whole virus.
We have constructed a recombinant plasmid using the C-terminal region of the non-structural V protein. Another recombinant plasmid using the C-terminal polypeptide of structural P protein was developed as a control. We succeeded in expressing the unique C-terminal part of the V protein in E. coli as a fusion protein with GST (GST-V), 40.8 kDa, as well as the C-terminal part of the P protein (GST-P), 55.4 kDa. Purified NDV-V and NDV-P proteins had sizes of 14.8 kDa and 29.4 kDa, respectively. The antigenicity of recombinant V protein was confirmed with Western blotting assay, which makes the using of this protein as a biological marker prospective.