In this study,ribonucleotide reductase gene of WSSV was amplified by PCR,digested by Sma I and Not I,and inserted into the expression vector pGEX-4T-2 to construct recombinant plasmid.Colonies with recombinant plasmid were picked for PCR and culture identified by enzyme digestion.The results show that ribonucleotide reductase gene is successfully inserted into the pGEX-4T-2 expression vector.After induced with IPTG at 18 ℃,the fusion protein is purified with Glutathione Sepharose 4B.

In this study, ferritin gene from Litopenaeus vannamei was amplified by PCR, digested by Sma I and Not I, and inserted into the expression vector pGEX-4T-2 to construct recombinant plasmid. Colonies with recombinant plasmid were picked for PCR and culture identified by enzyme digestion. The results show that ferritin gene ean be successfully inserted into the pGEX-4T-2 expression vector. After induced with IPTG at 18℃, the fusion protein can be purified with Glutathione Sepharose 4B.

The SOD gene was cloned by RT-PCR from colon carcinoma cell line Colo320. After digested by BamH I and Sma I, it was inserted into the plasmid pGEX-4T-2 with the right reading frame sequence to construct the expression vector, which can express the fusion protein with GST tag. The fusion protein was expressed after inducing with IPTG and purified for antibody preparation by Glutathione Sepharose affinity chromatography.

The Vp28 gene was cloned by PCR from White Spot Syndrome Virus.After digested by Not I and Sma I,it was inserted into the plasmid pGEX-4T-2 with the right reading frame sequence to construct the expression vector,which can express the fusion protein with GST tag.The fusion protein was expressed after inducing with IPTG at 18 ℃ for 24 h and purified for antibody preparation by Glutathione Sepharose affinity chromatography.