The envelope glycoprotein (GP5) is one of the major structural proteins of Porcine reproductive and respiratory syndrome virus (PRRSV). In this report, the N-terminal hydrophobic sequence of envelope glycoprotein gene (orf5) was deleted by PCR. The gene was subcloned into prokaryotic expressing vector pET-28 a(+) , the recombinant plasmid named pET-GP5 was transformed into E.coli cell BL21. SDS-PAGE and Western-blot indicated that the orf5 gene was expressed successfully and the recombinant fusion protein, which was about 20.8kDa, had immunologically reactive activity. The studies lay foundations for further study on the development of vaccines for PRRSV.
