Abstract：Abstract:Objective To clone cDNA of N-terminal fragment of bovine bactericidal /permeability-increasing protein(BPI), to construct the procaryotic expression vectors and to express the cDNA in E.coli , to purify recombinant protein.Methods According to the sequence of Genbank, the gene which encode bovine BPI protein were amplified by RT-PCR from mRNA that were extracted from the bovine polymorphonuclear neutrophils, then the gene was inserted into expression vector pGEX-4T-1.Recombinant plasmid was transformed into E.Coli BL21, which could produce fusion protein induced with IPTG.. RESULTS A 714 bp fragment was acquired.the E.coli transformed with recombinant plasmid was induced with IPTG., A 52KD expected protein of GST-BPI fusion protein was synthesized. CONCLUSION N-terminal of BPI was successfully expressed and purified.
