[Expression and biological function analysis of chicken aminopeptidase N].

To clone and express the gene encoding chicken aminopeptidase N (chAPN), and analysis the biological function of chAPN expressed in Escherichia coli (E. coli). The chAPN gene was amplified by RT-PCR from the kidney cells of chicken embryo and then cloned into the prokaryotic expression vector pCOLD-TF. Recombinant expression plasmid of pCOLD-TF-chAPN was constructed and then transformed into the competent E. coli BL21(DE3) cells for expression under different conditions such as induction time and inductor concentrations. Purified soluble recombinant chAPN was obtained by Ni-NTA His Bind Resin affinity chromatography and identified by SDS-PAGE gel and Western blotting assay. Its biological function was detected by its reaction with Leu-PNA and Enzyme-Linked Immunosorbent Assay (ELISA). The results showed that the expression product of chAPN gene in E. coli was soluble. It was able to bind infectious bronchitis virus (IBV) dose-dependently. In conclusion, chAPN gene has been successfully cloned and expressed in E. coli, which will establish a basis for further research the enzymatic activity and antiviral function.