Cloning and Expression E7 Protein Gene of Human Papillomavirus Type 11 in E. Coli

Objective To clone and express the gene encoding E7 protein of human papillomavirus type 11 (HPV11). Methods The gene encoding for E7 protein of HPV11 was amplified by PCR, cloned into vector PGEX-6P-1 to form PGEX-6P-1/E7 plasmid, and then transfected into the E. coli BL21. The GST-E7 fusion protein was expressed when induced by adding IPTG and purified with glutathione sepharose 4B affinity column. The GST portion of GST-E7 fusion protein was cleaved by thrombin. SDS-PAGE and Western blotting were used to detect the protein expression. Results The recombinant plasmid was identified and confirmed with enzyme digestion and sequencing. A high level expression of GST-E7 fusion protein was obtained and purified successfully. SDS-PAGE and Western blotting suggested that the E7 was a 11 000 molecular weight protein reacting with anti-E7 antibody. Conclusions Highly expressed E7 protein of HPV11 with high purity is obtained, which might be used for the study of its function, immunological analysis, and the study of the vaccine of genital warts.