Abstract: To construct the recombinant E.coli BL21 in which porcine β-defensin-2(pBD-2) could be stably expressed and the antimicrobial effect was evaluated. Based on cDNA sequence of porcine defensin pBD-2 gene reported in this study,five gene fragments were synthesized according to the codon preference of E.coli in this experiment. The pBD-2 gene was produced by gene splicing by overlap extension PCR(SOE PCR),and pBD-2 was inserted into expression vector (pET32a) and recombinant vector transformed into E.coli,where recombinant vector produced fusion protein successfully. The fusion and soluble induced protein were cut by enterokinase to get the recombinant pBD-2. Agarose diffusion assay showed that the pBD-2 had an antibacterial activity against Staphylococcus aureus. The pBD-2 was expressed successfully and casted a light for massive production of the pig defensin, a new antimicrobial agent.

Key words: porcine β-defensin-2; prokaryotic expression; fusion protein; antimicrobial activity