Purification of Glutathione S-transferase Fusion Proteins of SARS Coronavirus Spike Protein fragment 2 and Preparation of Anti-GST-S2 Polyclonal Antibody
Abstract: To study the immunogenicity of spike protein of SARS coronavirus, an expressional plasmid was constructed encoding partial sequence of SARS Coronavirus spike protein from 2170 bp to 2814bp, named fragment-2(S2). The gene sequence encoding S2 was amplified by RT-PCR from SARS Coronavirus genome RNA, cloned to pMD18-T vector and subcloned to pGEX-4T-2. E.coli JM109 that contained recombinant expression vector pGEX-S2 was amplified and fusion protein expression was induced by 1mmol/L IPTG at 37℃. Protein was extracted and purified by GSH-Sepharose affinity chromatography. After identified by the serum of SARS patient by Western-blot, the purified protein GST-S2 was used to immunize NIH mice three times at two weeks interval, the immunized mice produced high titer anti-GST-S2 polyclonal antibody. It lies a basis for the future study of subunit vaccine of SARS coronavirus.