Cloning, Expression, and in vitro Functional Activity Assay of phiC31 Integrase cDNA in Escherichia coli

OBJECTIVE The aim of present study was cloning and expression of phiC31 integrase cDNA in a bacterial expression vector. Thus, an intra molecular assay vector was applied to show in vitro activity of recombinant protein. MATERIALS AND METHODS In this experimental study, phiC31 cDNA was subcloned into a prokaryotic expression vector and transformed into E.coli Bl21 (DE3). Recombinant phiC31 integrase was purified form the bacterial cell lysates and its activity was verified by an in vitro functional assessment. RESULTS Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the purified phiC31 integrase confirmed the size of protein (70 kDa). Finally, the functionality of purified phiC31 integrase was verified. CONCLUSION The results of this study indicated that the purified integrase has a great potential application for in vitro site-specific integration.