Expression of Recombinant Fusion Protein of Newcastle Disease Virus from Escherichia coli Plasmid Clone C-2a by In-vitro Cell-free Protein Expression System

Department of Biochemistry and Molecular Biology, Faculty of Veterinary Medicine, Universitas Gadjah Mada, Jl.Fauna 2 Karangmalang, Yogyakarta 55281, Indonesia

^* Corresponding author: arisharyanto@ugm.ac.id

Abstract

Newcastle Disease Virus (NDV) is an infectious disease that infect many kinds of wild and domesticated birds. Infection of NDV become a massive problem for poultry industry around the world especially in Indonesia. Vaccination is an effort to prevent the infection of NDV in poultry. NDV vaccine that used in Indonesia is a conventional life vaccine from LaSota and B1 strains. These type of vaccine is 21%-23% genetically distinct with the virus that spread in the environment. The antibody protection provided by the vaccine is not effective. Therefore, vaccination with new local NDV strain is needed to prevent the NDV infection in Indonesia. The previously study research reported that the local isolate of NDV from Kulon Progo, Indonesia has been isolated. Fusion (F) protein encoding gene that has been inserted into pBT7-N-His expression p lasmid which isolated from clone C-2a of E. coli, then it was expressed by the Cell-free protein expression system. The aim of this study was to confirm whether clone C-2a of E.coli carrying a recombinant plasmid pBT7-N-His-Fusion NDV and to express a recombinant F protein of NDV in-vitro from expression plasmid by cell-free protein expression system. This work started by detection of recombinant plasmid pBT7-N-His-Fusion NDV by DNA plasmid extraction followed by agarose gel electrophoresis. The recombinant F protein was in-vitro expressed by cell-free protein expression kit. The expressed F protein of NDV then was visualized by SDS-PAGE and Westernblott to analyse the expression of NDV recombinant F protein. It confirmed that clone C-2a of E. coli contained plasmid pBT7-N-His (4.001 bp) inserted by recombinant F protein of NDV gene (642 bp). The visualisation of expressed recombinant F protein by SDS-PAGE and Westernblott showed the NDV recombinant F protein was a specific protein fragment with molecular weight of 25,6 kDa..