Abstract: Co-expressing the plasmid pET32a- pfu which was constructed using Infution technique with chaperone plasmid HG-PGRO7 at the same time in E. coli . BL21 (DE3) . The expression system, which expressed pfu gene alone in E. coli . BL21 (DE3) , was used as control .Most of unnecessary proteins were exenterated by heat treatment and (NH4 )2 S04 precipitation. The purified fusion protein was obtained by the Ni chelating resin affinity chromatography. The SDS-PAGE analysis showed that the molecular mass of the purified fusion protein was about 90 kD, conforming to the expected molecular mass of Pfu protein. The results of enzyme activity assay of pfu demonstrated that molecular chaperone was able to activate pfu gene expression and its enzyme activity .

Key words: Pfu