Cloning of 3D of Foot-and-mouth Disease Virus Strain AF72 and Its Expression in Escherichia coli

The 3D polymerase gene of Foot-and-mouth disease virus strain AF72 was amplified by reverse transcription polymerase chain reaction(RT-PCR),The purified PCR products were cloned into pGEM-T easy Vectors,and the nucleotide sequences were highly homologous to other four reference strains from GenBank.The target gene was cloned into the prokaryotic expression vector pET-30a(+),then recombinant expression plasmid pET-3D was transformed into E.coli BL21(DE3) competent cells,the target protein was highly expressed by IPTG induction.The protein was about 46 ku.Western blot showed specific reaction of the expressed product with type A FMDV antibody-positive serum,and the protein had nice reaction activity.