High Level Soluble Expressiion，One-Step Purification and Characterization of HIV-1 p24 Protein

The HIV 1 p24 gene (gag gene) was amplified by polymerase chain reaction (PCR) and cloned into an E.coli expression vehicle pQE30 between BamH I and Kpn I sites. After induction with IPTG, the transformed E.coli strain M15 expressed the HIV 1 p24 gene efficiently. The recombinant p24 protein was expressed as a soluble protein, composing 20% of the total protein. After onestep purification with Ni NTA + affinity chromatography, the protein was purified to almost homogeneity. When applied to ELISA, the p24 protein exhibited good specific reactivity with sera of HIV infected individuals. The antibodies against recombinant p24 protein from HIV infected plasma were purified and confirmed with HIV Western blot kit that the purified antibodies can only react with HIV 1 p24 antigen. It suggests that the recombinant HIV 1 p24 protein is suitable for assembling the HIV diagnostic kits.