Expression and Bioactivity Analysis of Porcine IL-2 in Pichia pastoris

A pair of primers was designed to clone IL-2 gene according to the codon bias principle and the recombinant expressed vector pPIC9k-IL-2 was constructed.The recombinant plasmid was transformed into P.pastoris GS115 by electroporation,the positive recombinant strains was screened with different G418 concentration and induced with methanol.The result showed that IL-2 gene was integrated with chromosome of P.pastoris by PCR identification.The expressed product had a molecular weight of 16 and 20 kD bands by SDS-PAGE analysis.The result of deglycosylation analysis indicated that the protein was glycosylated moderately.The protein was purified with sephadex column and had a bioactivity of lymphocyte proliferation.The Western blotting analysis showed that target protein had immunological activity.P.pastoris expressed system is an efficient way of production of pIL-2,the expressed product had a good bioactivity.