Abstract: BPI 600 bp gene which encode 193 amino acid fragments(rBPI₂₁)BPI N-terminal was amplified by RT-PCR from mRNA that were extracted from qHL-60; It was digested by EcoRI and BamHI to obtain BPI 400 bp and BPI 200 bp fragments.②PUC18-BPI200 and PUC18-BPI400 recombinant cloning vector were successfully constructed, and sequences were identical with those of the report. ③pBV-BPI600 recombinant expression vector was successfully constructed, It was transformated into the competent E. coli DH5α and BPI₂₁ recombinant protein was expressed by temperature induced method. The results of SDS-PAGE and Western blot has proved that the expressed recombinant protein is rBPI₂₁ which is encoded by BPI600 gene.

Key words: recombinant bactericidal/permeability increasing protein, pBV220 expression vector, PUC18 cloning vector