Expression and Analysis of Recombinant pIL-18 in Pichia pastoris
猪IL-18在毕赤酵母中的表达及活性分析

The porcine IL-18 gene was amplified from recombinant plasmid pGEM-IL-18 by PCR,then the pPIC9K-IL-18 of fusion expression vector was constructed by inserting IL-18 fragment,and was transformed to GS115 by electroporation,multi-copy recombinant strains were screened by G418.The expression of recombinant fusion protein was induced by methanol,SDS-PAGE was used to analyze expression product,fusion protein was purified by Sephadex G-100 column,bioactivity of IL-18 was measured by MTT assays.Experiment results show fusion protein of pIL-18 secreted by GS115,expression reaches the secretion peak of 160mg/L at 72h.We have expressed and purified successfully the recombinant pIL-18 with obvious biological activity in Pichia pastoris.